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ILLINOIS  BIOLOGICAL 
MONOGRAPHS 

Vol.  VI  October,  1920  No.  4 


Editorial  Committee 

Stephen  Alfred  Forbes  William  Trelease 

Henry  Baldwin  Ward 


Published  under  the 

Auspices  of  the  Graduate  School  by 

THE  University  of  Illinois 


CopnioaT,  1921  bt  the  Umvzssmr  or  Illinois 

DiSTKIBUTED  MaSCH  9,  1921 


THE  LARVAE  OF  THE 
COCCINELLIDAE 


WITH  SIX  PLATES 


BY 

J.  HOWARD  GAGE 


Contributions  from  the 
Entomological  Laboratories  of  the  Univerd^  of  minds 
No.  02. 


THESIS 

SUBMITTED    IN    PARTIAL    FULFILMENT    OF    THE    REQUIREMENTS    FOR    THE 

DEGREE  OF  MASTER  OF  SCIENCE  IN  ENTOMOLOGY 

IN  THE  GRADUATE  SCHOOL  OF  THE 

UNIVERSITY  OF  ILLINOIS 

1919 


TABLE  OF  CONTENTS 

PAGE 

Intxoduction 7 

Morphology 9 

Head 9 

Fixed  Parts  of  the  Head 9 

Movable  Parts  of  the  Head 13 

Thorax 17 

Prothorax 17 

Mesothorax  and  Metathorax 18 

Appendages 20 

Abdomen 21 

Armature  of  the  Body-wall 23 

Synopsis  of  Larvae 27 

Epilachninae 29 

Coccinellinae 31 

Chilocorini 32 

Coccinellini 34 

Microweiseini 42 

Scymnini 43 

Hyperaspini ., 45 

Bibliography 48 

Explanation  of  Plates 52 


239]  THE  LARVAE  OF  THE  COCCI NELLI DAE— GAGE 


INTRODUCTION 

The  adults  of  this  family  are  known  to  most  persons  as  lady-bugs  or 
ladybirds.  Their  distinctive  characteristics  are  the  apparently  three- 
segmented  tarsi  and  the  broad  hatchet-shaped  distal  segment  of  the 
maxillary  palpi.  Other  characteristics  are:  the  eleven  segmented  anten- 
nae, in  which  the  distal  segments  are  commonly  modified  to  form  a  more 
or  less  distinct  club-shaped  enlargement;  the  insertion  of  the  antennae 
near  the  mesal  margin  of  the  compound  eyes;  the  ventral  direction  of  the 
mouth;  the  retraction  of  the  head  into  the  small  transverse  prothorax; 
the  transverse  front  coxae;  the  closed  coxal  cavities,  except  in  Coccidula; 
the  convex  elytra;  and  the  abdomen  consisting  of  five  to  seven  exposed 
ventral  segments. 

Le  Baron  has  said,  in  speaking  of  this  family,  that  "The  Coccinellidae 
occupy  a  remarkably  anomalous  and  isolated  position.  Whilst  having 
the  rounded  form  of  the  plant  beetles,  the  clavate  antennae  of  the  scavan- 
gers,  and  the  dilated  palpi  of  the  fungus  beetles,  they  agree  in  food  and 
habits  with  none  of  these,  but  resemble  in  their  predaceous  habits  the 
ground  beetles  and  the  soft-winged  carnivora,  all  of  which  have  their 
bodies  more  or  less  elongated,  their  tarsi  five-jointed,  their  antennae  fili- 
form, and  their  palpi  slender  or  moderately  dilated." 

The  larvae  of  the  Coccinellidae,  though  they  may  be  known  to  many 
people,  are  not  as  a  rule  associated  with  the  adult  coccinellids  or  lady-bugs. 
The  most  distinctive  characteristics  of  these  larvae  are:  their  porcupine- 
like appearance;  elongated  body  which  is  usually  striped  or  mottled  with 
red,  black,  white  or  yellow  areas;  small  three-segmented  antennae;  power- 
ful mandibles;  and  the  habit  of  being  continually  on  the  move.  From  the 
systematist's  point  of  view  these  larvae  do  not  show  any  unusual  charac- 
teristics such  as  Le  Baron  has  noted  for  the  adults,  for  they  resemble  in 
most  respects  the  distinctly  predaceous  tjrpes  of  coleopterous  larvae. 
This  is  true  even  of  the  Epilachninae,  which  are  phytophagous.  With 
the  exception  of  this  subfamily  the  Coccinellidae  are  all  more  or  less  pre- 
daceous in  their  adult  stages,  and  almost  entirely  so  in  their  larval  stages. 

The  purpose  of  this  investigation  is  to  study  the  morphology  of  coc- 
cinellid  larvae  and  to  arrange  tables  for  the  identification  and  classification 
of  a  few  of  the  more  common  species.  The  work  has  been  limited  to  those 
genera  and  species  which  have  in  the  main  been  found  in  or  reported  from 
Illinois.  Specimens  were  collected  and  bred  during  the  autumn  of  1918, 
and  others  were  obtained  from  the  collections  of  Dr.  A.  D.  MacGillivray, 
the  University  of  Illinois,  the  Illinois  State  Natural  History  Survey,  and 
a  specimen  of  Brachyacantha  ursina  received  from  Cornell  University. 


8  ILLINOIS  BIOLOGICAL  MONOGRAPHS  [240 

The  investigation  of  the  immature  stages  of  insects  was  to  a  great 
extent  neglected  by  entomologists  until  about  the  beginning  of  the  twen- 
tieth century.  There  has  been  some  previous  work  done,  however,  upon 
the  immature  stages  of  the  Coccinellidae.  The  works  of  L.  Ganglbauer 
(1899),  Dimmock  (1906),  Palmer  (1914),  and  Boving  (1917)  are  valuable 
to  one  pursuing  a  study  of  the  immature  stages  of  these  beetles. 

I  am  greatly  indebted  to  Dr.  A.  D.  MacGillivray,  under  whose  super- 
vision this  work  was  carried  on,  for  the  interest  he  has  shown  at  all  times, 
for  the  use  of  specimens  from  his  collection,  and  for  the  privilege  of  using 
the  morphological  nomenclature  which  he  has  devised.  I  am  likewise 
indebted  to  Professor  S.  A.  Forbes  for  the  use  of  material  belonging  to  the 
Illinois  State  Natural  History  Survey,  and  to  Professor  J.  G.  Needham 
for  the  loan  of  material  from  Cornell  University. 


241]  THE  LARVAE  OF  THE  COCCINELLI DAE— GAGE 


MORPHOLOGY 

This  discussion  of  the  general  comparative  morphology  of  coccinellid 
larvae  is  based  for  the  most  part  upon  a  study  of  Chilocorus  hivulnerus. 
This  species  represents  the  most  generalized  condition  of  the  carnivorous 
coccinellids  that  I  have  studied.  A  still  more  generalized  condition  occurs, 
however,  in  the  subfamily  Epilachninae,  the  members  of  which  are  fof 
the  most  part  entirely  phytophagous. 

HEAD 

The  heads  of  coccinellid  larvae  are  symmetrical  and  the  general  outline 
is  circular  or  nearly  so,  except  in  the  genus  Microweisea  in  which  it  is  oval 
or  oblong.  In  Chilocorus  and  Epilachna  the  mouth  is  directed  ventrad; 
while  in  all  of  the  genera  of  the  Coccinellini,  Hyperaspini,  and  Microweis- 
eini  it  is  directed  caudo-ventrad.  The  greatest  departure  from  the  gen- 
eralized condition  is  found  in  Scymnus.  In  this  genus  the  mouth  is  directed 
cephalad.  For  the  sake  of  convenience  the  head  will  be  considered  under 
two  divisions;  first,  the  fixed  parts;  second,  the  movable  parts. 

Fixed  Parts  of  the  Head 

The  fixed  parts  of  the  head  consist  of  an  external  and  an  internal 
skeleton.  The  external  skeleton  is  composed  of  the  fused  front  and  post- 
clypeus,  preclypeus,  veterx,  labrum,  and  gula.  The  boundaries  of  these 
sclerites  are  marked  by  distinct  furrows  or  sutures.  The  internal  skeleton 
is  made  up  of  the  floor-like  tentorium,  which  in  the  Coccinellidae  consists 
of  three  parts. 

In  the  head  capsule  of  C.  bivulnerus  the  epicranial  suture  (Fig.  6,  es) 
is  present  on  the  meson.  It  extends  from  the  occipital  foramen  (Fig.  17, 
of)  to  a  point  on  the  cephalic  aspect  about  one-third  the  distance  from  the 
occipital  foramen  to  a  line  drawn  through  the  antennal  fossae.  This  part 
of  the  epicranial  suture  is  the  epicranial  stem  (Fig.  6,  es).  The  epicranial 
stem  bifurcates  at  its  ventral  end  and  the  two  epicranial  arms  (Fig.  6,  ea) 
extend  latero-ventrad  a  short  distance,  then  make  a  broad  curve  and 
extend  ventro-mesad  on  each  side  to  a  point  where  they  become  much 
thickened.  Each  thickening  is  a  pretentorina  (Fig.  6,  pt)  and  marks  the 
point  of  invagination  of  the  pretentorium.  The  epicranial  arms  curve 
broadly  laterad  and  ventrad  from  each  pretentorina  to  a  point  dorso- 
mesad  of  an  antennal  fossa  where  they  become  obsolete.  The  three 
sclerites  included  within  or  ventrad  of  the  fork  of  the  epicranial  stem  are 
the  fused  front  and  postclypeus  (Fig.  6,  fc)  and  the  labrum  (Fig.  6,  I). 
There  is  an  indistinct  furrow  which  marks  the  position  of  the  clypeal 


10  ILLINOIS  BIOLOGICAL  MONOGRAPHS  [242 

suture  (Fig.  6,  cs)  on  each  lateral  margin  of  the  head.  There  is  a  distinct 
precoila  (Fig.  6,  pel),  in  which  a  preartis  articulates,  located  on  each  side  of 
the  postclypeus  meso-ventrad  of  the  antennal  fossa  at  the  point  of  origin 
of  the  clypeal  suture.  The  vertex  occupies  all  of  the  dorsal  and  lateral 
parts  of  the  head  capsule  not  included  within  the  fork  of  the  epicranial 
suture  (Fig.  6,  v).  There  are  six  ocelli  (Fig.  6,  oc),  in  two  groups  of  three. 
Each  group  is  situated  on  the  lateral  margin  of  the  vertex  dorsad  and 
laterad  of  the  lateral  end  of  an  epicranial  arm.  The  antennal  fossae  are 
located  ventrad  of  the  ocelli  on  the  dorso-lateral  margin  of  the  vertex. 
The  large  somewhat  oval  opening  in  the  caudal  aspect  of  the  head  is  the 
occipital  foramen  (Fig.  17,  of). 

A  primitive  type  of  epicranial  suture  is  found  in  the  adults  of  Peri- 
planeta  and  the  larvae  of  Corydalis.  The  condition  of  the  epicranial  suture 
in  C.  bivulnerus  is  very  similar  to  that  of  these  primitive  forms,  except  that 
the  epicranial  stem  is  not  so  long  in  proportion  to  the  length  of  the  epi- 
cranial arms  and  that  a  portion  of  each  arm  is  wanting  near  the  antennal 
fossae.  This  suture  in  Epilachna  (Fig.  4,  es)  very  closely  resembles  that 
of  C.  bivulnerus,  but  the  epicranial  stem  is  much  longer  and  extends  almost 
one-half  the  distance  from  the  occipital  foramen  to  a  line  drawn  through 
the  antennal  fossae.  In  Megilla  the  epicranial  suture  (Fig.  7,  es)  is  present 
but  very  short,  not  extending  more  than  one-fifth  the  distance  from  the 
occipital  foramen  to  a  line  drawn  through  the  antennal  fossae;  while  in 
Adalia,  Anatis,  Hippodamia,  Coccinella,  and  Microweisea  the  epicranial 
stem  is  not  present  and  the  epicranial  arms  diverge  immediately  from  the 
occipital  foramen.  In  the  adult  larval  stage  of  Hyperaspis  the  epicranial 
suture  is  wanting,  but  it  is  present  in  the  first  instar.  The  epicranial  stem 
is  absent  in  the  second  instar,  but  the  epicranial  arms  are  present;  while 
in  the  later  larval  instars  the  entire  epicranial  suture  is  wanting.  The 
adult  larvae  of  Scymnus  (Fig.  14)  also  lack  an  epicranial  suture;  no  observa- 
tions were  made  on  the  conditions  present  in  very  young  larvae. 

The  epicranial  arms  are  present  in  most  coccinellid  larvae,  but  are 
absent  in  the  adult  larvae  of  Scymnus  and  Hyperaspis.  In  C.  bivulnerus 
the  epicranial  arms  extend  ventro-laterad  from  their  point  of  origin  to  a 
point  dorso-mesad  of  the  antennal  fossae.  In  Epilachna  the  epicranial 
arms  extend  ventrad  of  the  antennal  fossae,  but  do  not  extend  as  far 
laterad.  In  Chilocorus  and  Epilachna  the  epicranial  arms  are  not  widely 
divergent,  but  in  all  of  the  genera  of  the  Coccinellini  they  diverge  widely 
and  become  obsolete  slightly  ventrad  of  the  antennal  fossae.  In  the  first 
larval  instar  of  Hyperaspis  they  diverge  immediately  upon  the  dorso- 
cephalic  aspect  of  the  head,  the  epicranial  stem  being  very  short,  and  they 
extend  laterad  almost  parallel  with  the  caudal  margin  of  the  head,  make 
an  abrupt  turn  and  extend  laterad  and  ventrad  to  their  point  of  obsoles- 
cence.    In  Microweisea  (Fig.  13)  the  epicranial  arms  diverge  gradually 


243]  THE  LARVAE  OF  THE  COCCINELLIDAE—GAGE  11 

latere- ventrad  and  become  obsolete  dorsad  of  the  antennal  fossae.  Due 
to  the  extreme  length  of  the  head  in  this  genus,  these  arms  are  very  long. 
In  Scymnus  the  epicranial  arms  are  entirely  wanting. 

The  two  proximal  unpaired  sclerites  between  the  arms  of  the  epicranial 
suture  in  Corydalis  are  the  fused  front  and  post'clypeus.  These  areas  are 
separated  from  each  other  in  the  more  generalized  forms  by  the  fronto- 
clypeal  suture;  in  the  specialized  forms,  however,  they  may  become  com- 
pletely fused.  In  such  cases  the  fronto-clypeal  suture  is  absent,  but  por- 
tions of  it  may  be  indicated  by  a  furrow  on  each  lateral  portion  of  the  head. 
These  portions  extend  mesad  from  near  the  precoila.  In  C.  bivulnerus 
and  all  coccinellid  larvae  the  front  and  post-clypeus  (Fig.  6,  fc)  are  com- 
pletely fused  and  the  fronto-clypeal  suture  is  wanting.  The  clypeal  suture 
(Fig.  6,  cs)  is  indicated  by  an  indistinct  furrow  extending  mesad  from  the 
precoila  (Figs.  5  and  6,  pel).  The  area  ventrad  of  this  furrow  in  the  pre- 
clypeus  (Fig.  6,  pc)  and  the  area  dorsad  of  it  is  the  fused  front  and  post- 
clypeus  (Fig.  6,  fc).  In  Epilachna  (Fig.  4)  the  front  and  postclypeus  are 
entirely  separated  from  the  preclypeus  by  the  complete  clypeal  suture; 
while  in  all  of  the  other  genera  of  the  family  that  were  studied  the  condi- 
tion of  the  cljqjeal  suture  is  approximately  that  found  in  Chilocorus. 

The  labrum  of  C.  bivulnerus  is  the  distinct,  slightly  chitinized,  shield- 
like sclerite  attached  to  the  ventral  margin  of  the  preclypeus  (Fig.  6,  /). 
The  ventral  margin  of  the  labrum  may  be  slightly  emarginate  and  usually 
bears  four  or  six  medium-sized  setae.  In  general  the  structure  of  the 
labrum  in  all  of  the  coccinellids  studied  approximates  very  closely  the  con- 
dition found  in  the  labrum  of  C.  bivulnerus.  Its  general  shape,  however, 
varies  in  the  different  genera  of  the  family.  In  the  genus  Epilachna  the 
labrum  varies  most  widely  from  the  Chilocorus  type.  In  this  genus  it  is 
broadly  transverse  and  widely  but  shallowly  emarginate  on  the  ventral 
margin. 

The  vertex  of  C.  bivulnerus  (Fig.  6,  v)  consists  of  the  paired  continuous 
areas  on  the  cephalic  and  dorsal  aspect  of  the  head.  In  Chilocorus, 
Epilachna,  and  Megilla  the  epicranial  stem  is  present  and  marks  the  line 
of  separation  of  the  two  halves  of  the  vertex;  in  Hippodamia,  Coccinella, 
Anatis,  Adalia,  and  Microweisea  the  epicranial  arms  alone  are  present  and 
the  two  halves  of  the  vertex  do  not  meet  on  the  meson,  but  a  portion  of  the 
front  extends  between  them  to  the  occipital  foramen.  In  Hyperaspis  and 
Scymnus  the  epicranial  suture  is  absent  and  the  front,  postclypeus,  and 
vertex  are  fused.  The  vertex  is  continuous  on  its  lateral  and  caudo- 
lateral  margins  with  the  genae  (Fig.  5,  ge),  the  region  of  the  vertex  ventrad 
and  mesad  of  the  ocelli  and  the  antennal  fossae.  The  size,  shape,  and 
extent  of  the  vertex  is  dependent  upon  the  location  and  extent  of  the  epi- 
cranial suture. 


12  ILLINOIS  BIOLOGICAL  MONOGRAPHS  [244 

i4 
In  the  head  of  Corydalis  caudad  of  the  antennae  there  is  a  distinct 

ocularium  which  bears  five  or  six  ocelli.     This  indicates  the  position  of  the 

developing  compound  eyes.     In  C.  bivulnerus  the  ocelli  (Figs.  5  and  6,  oc) 

are  placed  three  on  each  lateral  aspect  of  the  head  dorsad  of  the  antennal 

fossae.     They  are  usually  arranged  in  the  form  of  a  triangle.     These  ocelli 

are  undoubtedly  the  homologues  of  the  ocelli  of  Corydalis  and  represent 

the  developing  compound  eye  of  the  adult.     The  arrangement,  number, 

and  position  of  the  ocelli  is  fairly  constant  in  all  of  the  genera  of  the  family. 

There  is  only  one  exception  worthy  of  note;  the  region  bearing  the  ocelli 

in  Scymnus  is  darkened  and  slightly  chitinized.     Two  of  the  ocelli  are 

equal  in  size,  while  the  third  is  almost  twice  as  large  as  either  of  the  others. 

In  generalized  insects  the  gula  is  present  as  a  distinct  chitinized  sclerite 
extending  cephalad  from  the  occipital  foramen  to  the  articulation  of  the 
maxillae  and  submentum.  It  is  bounded  on  its  lateral  margins  by  the 
postgenae.  In  all  of  the  larvae  of  the  Coccinellidae  the  gula  (Fig.  17,  g) 
is  present  as  a  more  or  less  membraneous,  rectangular,  glabrous  area  caudad 
and  dorsad  of  the  submentum. 

The  internal  skeleton  of  the  head  of  insects  is  formed  by  invaginations. 
It  serves  undoubtedly  to  make  the  head  more  rigid,  to  support  the  soft 
and  delicate  parts,  and  as  a  place  for  the  attachment  of  muscles.  The 
entire  internal  skeleton  of  the  head  is  known  as  the  tentorium  (Fig.  47). 
It  consists  of  two  or  three  pairs  of  arms  that  have  been  invaginated  from 
the  external  skeleton.  In  the  more  primitive  forms  there  may  be  only 
two  pairs.  In  all  of  the  larvae  of  the  Coccinellidae  there  are  three  distinct 
pairs  of  arms. 

The  pretentoria,  also  known  as  the  anterior  arms  of  the  tentorium 
(Fig.  47,  prt),  are  invaginated  on  the  dorsal  aspect  of  the  head  near  the 
point  where  the  epicranial  arms  turn  abruptly  laterad. 

The  supratentoria,  sometimes  called  the  dorsal  arms  of  the  tentorium 
(Fig.  47,  sup),  are  invaginated  mesad  of  the  antennal  fossae  and  are  well 
developed  in  the  larvae  of  the  Coccinellidae. 

The  metatentoria  or  the  posterior  arms  of  the  tentorium  (Fig.  47,  met) 
are  invaginated  on  the  ventral  aspect  of  the  head  near  the  articulations  of 
the  maxillae. 

In  many  insects  the  occipital  foramen  is  divided  into  two  parts  by  a 
distinct  bridge.  This  bridge  is  the  corpotentorium.  In  coccinellid  larvae 
the  corpotentorium  is  not  united  to  form  a  complete  bridge,  but  the  mesal 
boundaries  of  the  two  lobes  which  ordinarily  fuse  t6  form  the  corpoten- 
torium (Fig.  47,  cp)  approximate  each  other  very  closely  on  the  ventral 
aspect  of  the  head  and  are  located  much  nearer  the  mouth  than  the  occipi- 
tal foramen.  The  metatentoria  extend  dorsad  from  their  point  of  invagi- 
nation along  the  gular  sutures  toward  the  occipital  foramen  and  form 
important  landmarks  for  the  identification  of  the  gula.     When  they 


245]  THE  LARVAE  OF  THE  COCCI NELLI DAE— GAGE  13 

reach  the  occipital  foramen,  they  diverge  laterad  and  form  a  ring  around 
the  entire  opening. 

The  small  bridge-like  structure  about  one-half  way  between  the  lobes 
of  the  corpotentorium  and  the  occipital  foramen  is  the  laminitentorium 
(Fig.  47,  It).  It  is  formed  by  the  fusion  of  the  ends  of  the  pretentoria, 
supratentoria,  and  metatentoria. 

The  small  pit  on  the  ectal  surface  of  the  dorso-cephalic  aspect  of  the 
head  where  each  pretentorium  is  invaginated  is  a  pretentorina  (Fig.  4,  pt). 
The  point  on  the  ectal  surface  of  the  head  marking  the  place  of  invagi- 
nation of  each  supratentorium  is  a  supratentorina  (Fig.  6,  supt).  It  is  not 
present  as  a  pit  in  coccinellid  larvae.  The  metatentorina  is  the  point  of 
invagination  of  each  metatentorium  on  the  caudo-ventral  aspect  of  the 
head.     The  metatentorinae  are  not  indicated  by  a  pit  or  thickening. 

Movable  Parts  oj  the  Head 

The  form,  structure,  and  arrangement  of  the  movable  parts  of  the  head 
of  coccinellid  larvae  are  readily  homologized  with  the  movable  parts  of 
the  head  of  generalized  insects,  such  as  Periplaneta  or  the  larvae  of  Cory- 
dalis  or  the  adults  of  the  Carabidae.  The  movable  parts  consist  of  the 
antennae,  mandibles,  maxillae,  and  labium. 

The  antennae  of  C.  bivulnerus  (Fig.  36)  are  about  as  long  as  wide, 
slightly  conical,  and  composed  of  three  segments.  The  scape  (Fig.  36,  sc) 
is  cylindrical,  wider  than  long,  slightly  chitinized,  and  bears  a  few  fine  setae. 
The  scape  is  attached  to  the  heavily  chitinized  antennaria  which  bounds 
the  periphery  of  the  antennal  fossae  (Fig.  36,  ant)  by  a  delicate  membrane, 
the  antacoria  (Fig.  36,  ante).  The  pedicel  or  second  segment  (Fig.  36,  pd) 
is  distinctly  smaller  than  the  scape,  about  as  wide  as  long,  and  bears  a  dis- 
tinct long  seta  on  its  mesal  surface  near  the  distal  end.  It  also  bears  a 
small  number  of  fine  setae.  The  flagellum,  the  small  mound-like  segment 
on  the  distal  end  of  the  pedicel  (Fig.  36,  fl),  usually  appears  to  be  a  part  of 
the  pedicel,  but  careful  examination  shows  it  to  be  distinctly  separated 
from  it.  The  flagellum  usually  bears  three  peg-like  setae  which  are  prob- 
ably tactile  organs  (Fig.  36,  ts)  and  four  small  oval  openings  which  are 
probably  sensoria  (Fig.  36,  se). 

The  antennae  of  Epilachna  (Fig.  35)  are  about  three  times  as  long  as 
wide;  the  greater  part  of  the  elongation  is  found  in  the  pedicel.  In  this 
segment  the  peg-like  seta  at  the  distal  end  is  clearly  a  part  of  the  pedicel 
and  does  not  appear  as  a  part  of  the  flagellum  as  in  the  other  genera  of  the 
family.  In  all  of  the  genera  of  the  tribe  Coccinellini  and  in  the  genus 
Microweisea  the  antennae  are  less  than  twice  as  long  as  wide  and  the 
antacoriae  are  protuberant  and  might  easily  be  mistaken  for  the  first 
antennal  segment.  The  condition  of  the  remaining  parts  is  similar  to  that 
of  Chilocorus.     In  Hyperaspis  the  antacoria  (Fig.  38,  ante)  is  more  pro- 


14  ILLINOIS  BIOLOGICAL  MONOGRAPHS  [246 

tuberant  than  in  the  Coccinellini,  the  flagellum  is  more  mound-like,  and 
one  of  the  three  apical  setae  is  much  larger  than  the  other  two.  Scymnus 
(Fig.  39)  presents  a  type  of  antennae  that  shows  a  wide  variation  from  the 
type  found  in  the  other  genera  of  the  family.  The  antenna  of  this  genus 
is  wider  than  long,  only  slightly  chitinized,  scarcely  elevated,  and  conical. 
The  antacoria  (Fig.  39,  ante)  is  narrow;  the  scape  (Fig.  39,  sc)  is  about  three 
times  as  wide  as  long;  the  pedicel  (Fig.  39,  pd)  is  about  twice  as  wide  as 
long,  its  distal  end  much  narrower  than  the  proximal;  and  the  flagellum 
(Fig.  39,  fl)  is  more  or  less  mound-like  and  about  twice  as  wide  as  long. 

All  of  the  coccinellid  larvae  examined  have  well-developed  mandibles. 
They  may  be  of  a  crushing  type,  that  is  with  many  dentes  as  in  Epilachna, 
or  they  may  be  of  a  piercing  type,  that  is  with  one  or  two  dentes  as  in  all 
of  the  members  of  the  subfamily  Coccinellinae.  Within  the  family  there 
are  all  stages  of  variation  between  these  two  extremes.  The  type  of  man- 
dible found  in  such  generalized  genera  as  Periplaneta  or  Corydalis  is  that 
with  many  dentes.  This  tends  to  show  that  in  these  forms  the  mandible 
is  a  crushing  organ  primarily  and  not  for  piercing  as  appears  to  be  the  case 
in  the  specialized  coccinellid  larvae. 

The  mandible  of  C.  hivulnerus  (Figs.  40,  41)  is  of  moderate  size,  heavily 
chitinized,  somewhat  triangular  in  outline,  thick  and  heavy  at  the  proximal 
end,  and  tapering  to  a  bidentate  distal  point.  The  proximo-mesal  margin 
of  each  mandible  is  provided  with  a  distinct  wedge-shaped  mola  (Fig.  41, 
mo)  and  the  proximo-lateral  margin  with  a  stout  spine-like  seta.  On  the 
cephalo-mesal  margin  of  each  there  is  a  preartis  (Figs.  42,  41,  ps)  which 
articulates  in  a  precoila  (Fig.  5,  pel) ;  on  the  caudo-mesal  margin  there  is 
a  postartis  (Fig.  41,  poa)  which  articulates  in  a  postcoila.  The  mandibles 
of  Chilocorus  are  intermediate  in  form  between  the  two  extreme  types. 
The  majority  of  the  species  studied  have  mandibles  similar  to  those  of 
Chilocorus  and  tend  to  show  an  evolution  from  the  multidentate  type 
found  in  Epilachna,  which  are  entirely  phytophagous,  to  the  unidentate 
type  found  in  Hyperaspis,  Microweisea,  and  Scymnus,  which  are  entirely 
carnivorous.  In  all  of  the  genera  studied  the  mola  is  present,  but  it  is 
much  reduced,  is  almost  indistinguishable  in  Epilachna  (Fig.  42,  mo)  and 
shows  the  extreme  condition  of  its  reduction  in  Microweisea.  The  mandi- 
bles of  all  coccinellid  larvae  are  connected  with  the  head  capsule  cephalad 
and  ventrad  of  the  antennal  fossae  by  a  small  and  distinct  membrane. 
This  membrane  is  the  mandacoria  (Fig.  5,  mco).  The  extensor  muscles 
are  attached  to  the  lateral  margin  of  the  mandible  between  the  preartis 
and  the  postartis,  while  the  retractor  muscles  are  attached  near  the  mesal 
portion  of  the  mandible. 

The  maxillae  of  the  Coccinellidae  show  a  greater  degree  of  departure 
from  the  primitive  type  than  any  other  of  the  movable  parts.  They 
resemble  in  general  form  the  maxillae  of  Periplaneta  and  the  larvae  of 


247]  THE  LARVAE  OF  THE  COCCINELLI DAE— GAGE  IS 

Corydalis,  but  show  a  more  striking  resemblance  to  the  conditions  found 
in  the  maxillae  of  carabid  larvae.  Though  the  coccinellid  maxillae  are 
similar  in  form  to  those  of  Periplaneta  or  to  those  of  the  larvae  of  Corydalis, 
they  also  show  a  great  difference  in  structure  and  are  much  more  specialized 
than  those  of  carabid  larvae.  In  order  to  homologize  the  parts  of  the 
maxilla,  it  was  necessary  to  trace  the  development  of  this  appendage  from 
the  more  generalized  to  the  more  specialized  condition.  In  the  tracing  of 
this  development  maxillae  of  the  larvae  of  Carabidae,  Lachnosterna, 
Elateridae,  and  Curculionidae  were  found  most  useful. 

Each  maxilla  of  C  bivulnerus  is  moderately  large,  slightly  chitinized, 
and  consists  of  the  following  parts:  a  fused  cardo  and  stipes,  a  palpifer, 
a  maxillary  palpus,  and  a  galea.     The  lacinia  is  apparently  wanting. 

In  the  primitive  type  of  coleopterous  larvae  the  cardines  are  composed 
of  two  sclerites;  the  subcardo,  which  articulates  with  the  postcoila  and  a 
second  sclerite,  the  alacardo,  which  lies  between  the  subcardo  and  stipes. 
This  condition  is  found  in  the  larvae  of  Pterostichus  and  Lachnosterna; 
while  in  the  larvae  of  a  curculionid  beetle,  Phytonomus,  the  subcardo  and 
alacardo  are  fused.  A  similar  condition  is  found  in  the  larvae  of  the  Ela- 
teridae. In  the  Coccinellidae  the  subcardo  and  alacardo  are  not  only 
fused  to  form  the  cardo,  but  the  cardo  and  stipes  are  fused  and  the  extent 
of  the  cardo  is  only  indicated  by  small  and  in  many  cases  indistinct  notches 
along  the  sides  of  the  fused  cardo  and  stipes.  This  indication  of  the.suture 
between  the  cardo  and  stipes  is  found  in  the  maxillae  of  all  of  the  larvae 
studied  and  there  is  but  little  variation  shown.  It  will  be  seen  from  the 
above  that  the  stipes  and  cardo  must  be  discussed  as  one  sclerite.  This 
sclerite  (Fig.  18,  ss-{-ca)  occupies  the  area  at  the  proximal  end  of  the  maxilla 
cephalad  or  ventrad  of  the  gula.  Its  form  in  C.  bivulnerus  is  that  of  a 
rectangle.  It  is  about  as  wide  as  long,  slightly  setaceous,  and  chitinized. 
This  general  form  of  the  stipes  and  cardo  is  found  in  all  of  the  genera 
studied  except  Microweisea,  Scymnus,  and  Hyperaspis.  In  these  genera 
the  stipes  and  cardo  are  narrow  and  elongated.  In  Microweisea  and 
Hyperaspis  the  proximal  end  is  curved  laterad.  This  curved  portion 
represents  the  cardo  and  the  remaining  part  of  the  sclerite  is  the  stipes. 

The  palpifer  is  present  as  a  distinct  shoulder-like  area  (Fig.  IS,  pf)  near 
the  distal  margin  of  the  fused  stipes  and  cardo.  Its  form  and  position  are 
generally  constant  in  all  of  the  genera  studied.  This  area  bears  at  its 
distal  extremity  the  three-segmented  maxillary  palpus.  The  maxillary 
palpus  (Fig.  18,  tnxpl)  is  well  developed  in  all  of  the  genera.  In  C.  bivuU 
nerus  they  are  stout  and  slightly  chitinized.  The  first  segment  is  cylindri- 
cal, wider  than  long,  and  usually  with  one  or  two  small  setae.  The  second 
segment  is  longer  than  wide  and  with  one  or  two  large  setae.  The  third 
segment  is  conical,  about  one-half  as  long  as  wide  with  two  or  three  setae 
and  with  a  group  of  sensory  organs  at  its  distal  end.     The  maxillary  palpus 


16  ILLINOIS  BIOLOGICAL  MONOGRAPHS  [248 

in  Epilachna  (Fig.  16,  mxpl)  is  much  elongated,  the  proximal  segment  is 
nearly  twice  as  long  as  wide,  the  second  segment  more  than  twice  as  long 
as  wide,  and  the  conical  third  segment  nearly  three  times  as  long  as  wide. 
In  all  of  the  other  genera  the  maxillary  palpus  resembles  that  of  C.  hivul- 
nerus  and  the  distal  segment  of  each  bears  a  group  of  peg-like  organs, 
tactile  setae. 

The  galea  (Fig.  18,  go)  in  C.  bivulnerus  is  the  broad  triangular  area  dis- 
tad  of  the  palpifer.  Its  shape  and  structure  is  more  or  less  constant 
throughout  the  family,  the  most  notable  exception  being  found  in  Hyperas- 
pis  (Fig.  27,  ga).  In  this  genus  the  galea  is  rounded  and  appears  to  be 
more  or  less  sponge-like  and  bears  a  few  setae.  In  Epilachria  (Fig.  16, 
ga)  the  distal  margin  of  the  galea  is  densely  setaceous,  while  in  all  of  the 
other  genera  of  the  family  it  bears  only  a  few  setae.  There  is  a  peg-like 
structure  on  the  galea  that  bears  a  striking  resemblance  to  the  distagalea; 
this  is  nothing  more  than  a  tactile  seta  and  cannot  be  interpreted  as  a 
distagalea. 

The  mesal  margins  of  the  maxillae  and  the  lateral  margins  of  the  labium 
are  connected  in  all  of  the  genera  by  a  distinct  membrane,  the  labiacoria 
(Fig.  18,  lie).  The  lateral  margins  of  the  maxillae  and  the  mandibles  are 
connected  by  a  similar  membrane,  the  maxacoria  (Fig.  18,  mxc).  An 
extension  of  the  maxacoria  connects  the  stipes  and  cardo  of  each  side  to  a 
postgena. 

The  labium  of  coccinellid  larvae  differs  considerably  from  that  found 
in  the  more  primitive  forms,  as  the  larvae  of  Corydalis  and  the  adults  of 
Periplaneta.  Many  of  the  parts  seem  to  be  lacking.  The  type  of  labium 
found  in  the  more  generalized  coleopterous  larvae  shows  but  little  resem- 
blance to  the  coccinellid  labium.  By  a  study  of  the  labia  of  the  primitive 
forms  named  and  of  the  more  generalized  Coleoptera,  one  is  able  to  homol- 
ogize  the  parts. 

The  labium  of  C.  bivulnerus  is  the  more  or  less  membraneous  area 
cephalad  and  ventrad  of  the  gula  and  between  the  maxillae.  It  appears 
to  be  made  up  of  two  parts,  the  submentum  (Fig.  18,  su)  and  the  ligula 
(Fig.  18,  lig.).  The  mentum  is  indistinguishable  or  fused  with  the  ligula. 
The  submentum  (Fig.  18,  su)  is  the  ^arge  proximal  portion.  It  is  mem- 
braneous, more  or  less  rectangular,  usually  with  four  setae,  two  large  ones 
which  decussate,  and  two  smaller  ones.  In  Anatis,  Megilla,  Coccinella, 
and  Hippodamia  there  may  be  many  setae  on  the  submentum,  the  number 
varying  from  four  in  Hippodamia  convergens  to  eighteen  in  Anatis.  The 
submentum  is  not  clearly  or  distinctly  separated  from  the  ligula  in  C. 
bivulnerus  but  there  is  a  distinct  division  between  the  two  in  Epilachna 
(Fig.  16),  while  in  Hyperaspis  (Fig.  27)  the  division  between  the  ligula  and 
submentum  is  entirely  obsolete.  In  all  of  the  other  genera  studied  the 
condition  of  this  division  approximates  that  found  in  Chilocorus.     The 


2491  THE  LARVAE  OF  THE  COCCINELLJDAE—GAGE  17 

ligula  is  the  distal  portion  of  the  labium.  In  C.  bivtdnerus  it  is  composed 
of  the  fused  stipulae,  glossae,  and  paraglossae.  Near  the  ventro-lateral 
margin  there  is  a  distinct  shoulder-like  swelling,  the  palpiger  (Fig.  18,  pg), 
which  bears  a  two-segmented  labial  palpus  (Fig.  18,  lipl).  There  is  a 
heavy,  semicircular,  chitinous  band  (Fig.  18,  cb)  that  surrounds  each  pal- 
piger which  probably  serves  to  increase  its  rigidity.  Each  labial  palpus 
consists  of  two  segments.  The  proximal  segment  is  short,  as  wide  as  long; 
while  the  distal  segment  is  conical  and  bears  a  group  of  tactile  setae  at  its 
distal  end.  The  ligula  also  bears  four  to  six  moderately  large  setae.  The 
type  of  ligula  found  in  C.  hivulnerus  is  remarkably  constant  within  the 
family,  the  only  notable  variation  being  found  in  Hyperaspis,  where  the 
labial  palpi  have  been  reduced  to  a  single  dome-like  segment  which  bears  a 
few  tactile  setae  (Fig.  27,  lipl). 

THORAX 

That  part  of  the  body  caudad  of  the  head  consists  of  thirteen  segments. 
The  dorsal  surface  of  the  segments  is  convex  and  the  ventral  surface  con- 
cave or  flattened.  They  may  be  provided  with  scoli,  senti,  parascoli, 
strumae,  verrucae,  or  chalazae  and  setae.  The  variation  in  the  type  of 
armature  will  be  taken  up  later.  The  first  three  segments  constitute  the 
thorax  and  the  remainder  the  abdomen.  In  all  of  the  genera  of  the  family 
the  thoracic  segments  are  distinctly  separated  from  each  other  by  a  deep 
coria,  more  distinct  on  the  ventral  than  on  dorsal  surfaces. 

Prothorax 

The  prothorax  of  C.  hivulnerus  (Figs.  1,  2  and  3,  prth)  is  about  two-thirds 
as  long  as  the  mesothorax  and  metathorax  combined.  The  same  is  true 
of  Epilachna,  Microweisea,  Scymnus,  and  Hyperaspis;  while  in  all  of  the 
genera  of  the  Coccinellini  the  prothorax  is  about  one-half  as  long  as  the 
other  thoracic  segments  together. 

The  tergum  is  usually  convex  and  oval  in  outline  when  viewed  from 
above  (Figs.  1  and  2,  t).  In  C.  bivulnerus  the  greater  part  of  the  dorsum 
is  covered  with  a  dark  heavily  chitinized  dorsal  shield  from  which  the 
cone-like  senti  project.  This  shield  is  formed  by  the  fusion  of  pinacula  and 
its  surface  bears  numerous  fine  setae.  The  dorsal  shield,  when  viewed  from 
above,  appears  to  be  rectangular  in  outline  and  is  divided  into  two  parts 
by  a  slender  white  line  extending  along  the  dorso-meson.  The  senti  are 
arranged  in  three  distinct  groups,  a  cephalic  group  of  six  placed  in  a  trans- 
verse row  near  the  cephalic  margin,  a  lateral  group  of  one  placed  near  the 
middle  of  each  lateral  margin,  and  a  caudal  group  of  one  placed  near  the 
middle  of  each  half  upon  the  caudal  margin.  In  Epilachna  the  dorsal 
shield  does  not  cover  such  a  large  portion  of  the  dorsum.  It  is  more  or 
less  oval  in  outline  and  bears  only  the  cephalic  row  of  four  scoli.    Its  sur- 


18  ILLINOIS  BIOLOGICAL  MONOGRAPHS  [250 

face  is  also  covered  with  short  fine  setae.  In  all  of  the  genera  of  the  Coc- 
cinellini  the  dorsal  shield  is  large  and  covers  the  greater  part  of  the  dorsal 
aspect.  It  is  not  so  heavily  chitinized  as  in  Chilocorus  and  is  divided 
longitudinally  into  four  plates.  Two  of  these  are  adjacent  on  the  dorso- 
meson  and  each  bears  three  or  more  large  chalazae  and  many  small 
setae.  The  lateral  plates  are  smaller  than  the  mesal  and  bear  a  fringe  of 
large  chalazae  on  their  lateral  and  cephalic  margins.  In  Microweisea  and 
Scymnus  the  dorsal  shield  is  only  indicated  and  very  slightly  chitinized. 
It  appears  to  extend  over  the  larger  part  of  the  dorsum  and  bears  several 
large  black  setae.  These  are  arranged  in  three  transverse  rows,  a  row  on 
the  cephalic  and  caudal  margins  and  another  midway  between  them.  In 
Hyperaspis  the  dorsal  shield  is  wanting  and  the  tergum  is  only  slightly 
chitinized.  It  is  traversed  by  three  rows  of  prominent  black  setae  arranged 
as  in  Scymnus  and  Microweisea.  There  are  in  addition  to  these  larger 
setae,  many  smaller  and  inconspicuous  ones. 

The  pleural  area  in  C.  bivulnerus  is  the  more  or  less  reduced  area  ven- 
trad  of  the  dorsal  shield  (Fig.  2,  prpl).  It  extends  ventrad  to  the  sternal 
area.  There  is  a  small  group  of  setae  cephalo-dorsad  of  the  procoxacoila 
in  most  of  the  genera  studied.  This  is  the  only  group  of  setae  located  on 
the  lateral  aspect  of  the  prothorax. 

The  prosternum  of  Chilocorus  is  the  rectangular  area  located  between 
the  coxal  fossae.  There  has  been  much  controversy  among  morphologists 
as  to  the  number  of  sclerites  in  this  area.  It  is  not  my  purpose  to  discuss 
this  question,  there  are,  however,  a  few  landmarks  of  this  region  that  must 
be  considered.  In  all  of  the  species  studied  there  is  a  small  pit,  the  fur- 
dna,  (Fig.  3,  fur)  found  near  the  meso-caudal  boundary  of  each  procoxa- 
coria.  There  is  a  distinct  ridge  extending  between  these  pits  which  prob- 
ably serves  as  a  place  for  the  attachment  of  muscles.  The  prosternum  of 
Chilocorus,  Epilachna,  Microweisea  and  Hyperaspis  usually  bears  a  few 
small  setae  and  chalazae  just  cephalad  of  the  procoxacoria,  while  in  all  of 
the  genera  of  the  Coccinellini  it  bears  two  distinct  verrucae  which  are 
located  adjacent  to  the  meson. 

Mesothorax  and  Meiaihorax 

In  general  the  mesothorax  and  metathorax  of  coccinellid  larvae  are  so 
nearly  similar  that  a  single  description  will  suffice  for  both  of  them.  Each 
of  these  segments  is  wider  than  long,  but  in  other  respects  they  are  similar 
to  the  prothorax  in  form. 

The  mesotergum  in  C  bivulnerus  (Fig.  1,  mst)  is  distinctly  longer  and 
narrower  than  the  metatergum  (Fig.  1,  mtt).  In  practically  aU  of  the 
genera  of  the  Coccinellini  the  mesotergum  and  metatergum  are  subequal 
in  length,  but  the  metatergum  is  as  a  rule  wider  than  the  mesotergum.  In 
Microweisea,  Scymnus,  and  Hyperaspis  the  mesotergum  is  longer  and 


251]  THE  LARVAE  OF  THE  COCCI NELLJ DAE— GAGE  19 

narrower  than  the  metatergum.  The  mesotergum  and  metatergum  of 
C.  bivulnerus  do  not  bear  dorsal  shields.  Each  tergum  bears  a  transverse 
row  of  four  senti,  the  pinacula  of  which  are  distinct  and  never  fused. 
The  median  senti  are  much  smaller  than  the  lateral  ones.  In  Epilachna 
there  is  a  small  median  dorsal  shield  from  which  two  scoli  project,  these 
scoli  originate  so  close  together  that  they  seem  to  be  the  two  forks  of  a 
single  scolus.  In  all  of  the  genera  of  the  Coccinellini  the  dorsal  shield  is 
present  on  the  mesotergum  and  metatergum  as  a  raised  oval  area  which 
covers  the  larger  part  of  the  dorsum.  The  mesal  margin  of  this  shield 
bears  a  pair  of  small  parascoli,  while  the  lateral  margin  bears  a  large  para- 
scolus.  The  surface  of  the  shield  is  densely  covered  with  fine  setae  and  in 
the  genera  Coccinella,  Hippodamia,  and  Anatis  also  bears  chalazae.  In 
Scymnus  and  Microweisea  the  dorsal  shield  is  weakly  chitinized,  covers 
the  larger  part  of  the  dorsum,  and  bears  a  small  verruca  on  each  side  of  the 
meson.  Hyperaspis,  on  the  other  hand,  has  no  dorsal  shield  nor  is  there 
any  chitinization  to  suggest  the  presence  of  a  shield.  The  terga  bear  many 
long,  black,  prominent  setae  which  are  arranged  in  more  or  less  transverse 
rows;  one  row  on  the  cephalic  and  one  on  the  caudal  annulet  of  each 
segment. 

The  pleural  areas  of  the  mesothorax  and  metathorax  of  all  of  the  species 
studied  are  well  developed.  They  are  the  lateral  vertical  areas  between 
the  terga  and  the  sterna  (Fig,  2,  mspl,  mtpl).  In  C.  bivulnerus  the  meso- 
pleural  area  is  much  larger  than  the  metapleural;  this  is  also  the  case  in 
Microweisea,  Scymnus,  and  Hyperaspis.  In  Epilachna  the  metapleural 
area  is  larger  than  the  mesopleural;  while  in  all  of  the  genera  of  the  Coc- 
cinellini they  are  subequal.  The  ventral  portions  of  the  mesopleural  and 
metapleural  areas  are  obliquely  crossed  by  a  furrow  extending  caudo- 
mesad  from  the  coxacoila.  In  C.  bivulnerus  the  mesopleural  area  bears 
two  subequal  senti,  one  near  the  cephalic  and  one  near  the  caudal  margin; 
the  base  of  each  of  these  senti  is  provided  with  a  small  pinaculum.  The 
metapleural  area  bears  two  senti,  but  the  cephalic  one  is  much  smaller 
than  the  caudal.  In  Epilachna  the  cephalic  area  bears  a  few  small  setae, 
while  the  caudal  one  bears  the  large  scolus.  In  the  Coccinellini  the 
cephalic  area  usually  bears  a  few  small  setae,  and  the  caudal  one  is  pro- 
vided with  a  parascolus  in  Hippodamia,  Coccinella,  and  Anatis;  while  in 
Megilla  and  Adalia  this  area  bears  a  struma.  In  Microweisea,  Scymnus, 
and  Hyperaspis  the  cephalic  area  is  smaller  than  the  caudal  area  which 
bears  a  small  verruca  in  the  two  former,  and  a  few  fine  setae  in  the  latter. 

The  mesosternum  and  metasternum  are  so  nearly  similar  to  the  pro- 
sternum  that  no  description  is  necessary. 

In  C.  bivulnerus  the  mesothoracic  spiracle  is  located  in  the  small  tri- 
angular area  lying  between  the  mesotergum  and  the  mesopleural  area,  the 
protopleurite  (Boving  1917).     This  condition  is  also  found  in  all  of  the 


20  ILUNOIS  BIOLOGICAL  MONOGRAPHS  [252 

members  of  the  Coccinellini  and  Epilachna;  while  in  Micro weisea,  Sc>Tn- 
niis,  and  Hyperaspis  the  mesothoracic  spiracle  is  not  located  on  the  tergum, 
or  protopleurite,  as  Boving  points  out,  but  distinctly  in  the  mesocoria. 
The  metathoradc  spiracles  are  rudimentary  or  entirely  wanting. 

Appendages 

The  thorax  of  all  coccinellid  larvae  bears  three  pairs  of  legs.  One  pair 
is  attached  to  each  segment.  They  are  well  developed  and  fitted  for  walk- 
ing or  clasping  the  surface  of  the  leaves  and  stalks  upon  which  the  larvae 
are  usually  found.  Since  the  general  form  and  structure  of  each  pair  of 
legs  is  the  same,  their  only  difference  being  that  of  size,  a  description  of  a 
single  prothoracic  leg  will  suffice  for  all.  The  mesothoracic  and  meta- 
thoradc legs  are  subequal  and  slightly  longer  and  wider  than  the  pro- 
thoradc  legs.  Each  leg  is  about  as  long  as  the  body  is  wide,  except  in 
very  yoimg  larvae  in  which  they  are  distinctly  longer.  In  adult  larvae 
they  are  comparatively  stout  and  fitted  for  clasping.  The  coxal  fossae 
are  the  circular  or  oval  holes  in  the  sternum  in  which  the  legs  are  inserted. 
The  coxa  are  attached  to  the  coxal  fossae  by  a  distinct  membrane,  the 
coxacoria.  There  is  a  distinct  coxacoila  on  the  lateral  margin  of  each 
coxal  fossa  in  which  the  coxa  articulates.  The  procoxa  (Figs.  2  and  3, 
pre)  is  subcylindrical,  short,  tapering  toward  the  distal  end  and  bears  a 
few  scattered  but  prominent  setae.  The  protrochanter  (Figs.  2,  3,  prUr) 
is  short,  triangular,  the  ventral  surface  the  longer  and  bears  a  prominent 
group  of  coarse  setae.  The  profemur  (Fig.  3,  prfr)  is  short,  about  twice  as 
long  as  wide,  with  its  dorsal,  caudal,  and  cephalic  surfaces  sparsely  setace- 
ous. This  condition  of  the  femur  is  found  in  Chilocorus  and  Hyperaspis; 
while  in  Epilachna  and  all  of  the  genera  of  the  Coccinellini,  and  the  genera 
Microweisea,  and  Scymnus,  the  femur  is  at  least  three  times  as  long  as  wide. 
The  protibia  (Figs.  2,  3,  prii)  is  about  as  long  as  the  profemur,  one-third 
as  wide  as  long,  and  tapering  distinctly  toward  the  distal  end.  The 
cephalic,  caudal,  and  dorsal  surfaces  of  the  proximal  two-thirds  are  densely 
setaceous;  while  the  entire  surface  of  the  distal  one- third  is  densely  covered 
with  dub-shaped  setae  or  tenent  hairs  (Fig.  43,  U).  The  tenent  hairs  are 
very  numerous  in  Chilocorus,  Epilachna,  and  all  of  the  genera  of  the 
Coccinellini;  while  in  Scynmus  and  Hyperaspis  there  are  only  a  few,  five 
to  ten,  on  each  tibia,  and  in  Microweisea  there  are  only  two  which  are  very 
broad,  flat,  elongated,  and  paddle-like  (Figs.  44,  45).  The  protarsus 
(Figs.  2,  3,  prta)  consists  of  a  single  short  triangular  segment  which  bears 
a  few  tenent  hairs.  Its  distal  margin  is  provided  with  a  sickle-shaped 
daw  (Figs.  4,  3,  prd).  This  claw  is  provided  with  a  short,  blunt  appendic- 
ulated  tooth  on  its  proximo-ventral  angle,  and  it  probably  serves  as  an 
aid  in  clasping  surfaces.  There  is  some  variation  in  the  general  shape 
of  the  tarsal  daw  in  the  various  genera  of  the  family  and  this  characteristic 
serves  as  a  means  of  separating  them. 


253]  THE  LARVAE  OP  TEE  COCCI NELLI DAE— GAGE  21 

ABDOMEN 

The  abdomen  of  all  coccinellid  larvae  is  composed  of  ten  segments 
which  are  connected  by  more  or  less  distinct  coria.  This  coria  is  usually- 
more  prominent  on  the  ventral  than  on  the  dorsal  aspect.  The  abdomen 
is  generally  subdepressed,  widest  on  its  cephalic  half,  and  tapering  on  its 
caudal  half.  The  abdomen  in  C.  bivulnerus  narrows  gradually  toward  the 
caudal  end.  The  first  three  segments  are  about  as  wide  as  the  metathorax. 
This  is  also  true  of  Epilachna  and  of  all  of  the  genera  of  Coccinellini  in 
which  the  first,  second,  third,  and  fourth  abdominal  segments  are  subequal 
in  width.  The  remaining  abdominal  segments  become  narrower  toward 
the  caudal  end.  In  Microweisea  and  Scymnus  the  first,  second,  and  third 
abdominal  segments  are  the  widest;  caudad  of  the  third  the  abdomen 
becomes  narrower.  In  Hyperaspis  the  first,  second,  fifth,  and  sixth  seg- 
ments are  subequal  in  width;  while  the  third  and  fourth  are  the  widest 
segments  in  the  body. 

In  C.  bivulnerus  the  first  abdominal  segment  is  slightly  narrower  and 
shorter  than  the  metathorax.  Its  tergum  (Figs.  1,  2)  bears  four  distinct 
senti  arranged  in  a  transverse  row.  The  dorsal  senti  are  adjacent  on  the 
dorso-meson  and  the  dorso-lateral  ones  are  placed  on  each  side  near  the 
lateral  margin  of  the  tergum.  There  is  a  small  circular  pinaculum  at  the 
base  of  each  sentus.  The  dorsal  pinacula  are  brown  or  yellow  colored  and 
the  dorso-lateral  ones  are  white.  There  is  also  a  few  inconspicuous  setae 
on  the  surface  of  each  pinaculum.  The  lateral  aspect  is  a  vertical  area, 
almost  square,  and  bears  the  large  lateral  sentus,  at  the  base  of  which  there 
is  a  very  large  pinaculum  nearly  covering  the  entire  surface.  The  para- 
lateral  group  is  wanting.  The  sternum  (Fig.  3,  st)  is  about  as  long  as  the 
tergum.  The  coria  between  it  and  the  metatergum  is  not  at  all  distinct. 
The  cuticle  is  thin  and  membraneous  and  bears  two  groups  of  small  ventral 
setae  adjacent  to  the  ventro-meson.     The  ventro-lateral  setae  are  wanting. 

The  external  structure  of  segments  two  to  five  inclusive  is  similar, 
however,  each  succeeding  segment  is  narrower  than  the  preceding  one. 
The  coriae  between  the  segments  are  distinct.  Each  tergum  has  four 
senti  arranged  in  a  transverse  row.  The  dorsal  senti  and  their  pinacula 
are  adjacent  to  the  dorso-meson;  the  dorso-lateral  senti  are  located  in  a 
position  similar  to  those  of  the  first  abdominal  segment.  All  of  the  pina- 
cula are  dark  brown  in  color  and  bear  numerous  fine  setae.  Each  lateral 
aspect  is  almost  square  and  bears  a  distinct  lateral  sentus.  The  pinacula 
at  the  base  of  these  senti  are  small.  In  the  second  and  third  segments 
ventrad  of  the  lateral  senti  there  is  a  solitary  small  seta;  while  in  segments 
four  and  five  there  is  a  prominent  chalaza  surrounded  by  a  group  of  small 
setae.  This  group  represents  the  paralaterals.  Each  sternum  is  as  long 
as  its  respective  tergum  and  the  coriae  between  the  sterna  are  distinct. 
The  cuticle  is  thin  and  membraneous  and  bears  on  each  sternum  four  groups 


22  ILUNOIS  BIOLOGICAL  MONOGRAPHS  [254 

of  chalazae  arranged  in  a  transverse  row;  those  near  the  meson  are  the 
ventral  chalazae  and  those  on  the  lateral  margin  are  the  ventro-laterals. 
Each  chalaza  is  surrounded  by  a  small  group  of  setae. 

The  sixth,  seventh,  and  eighth  abdominal  segments  are  as  long  as  the 
preceeding  but  narrower.  The  pinacula  at  the  bases  of  the  dorsal  senti 
have  become  fused  on  their  mesal  margins  and  appear  to  be  dumb-bell- 
shaped.  The  dorso-lateral  senti  are  shorter  than  those  of  the  preceding 
segments  and  their  pinacula  are  very  much  reduced.  The  lateral  aspect 
of  each  of  these  segments  is  similar  to  that  of  the  preceding,  except  that 
it  is  considerable  smaller.  There  is  a  small  lateral  sentus  with  a  very  small 
pinaculum  on  the  lateral  aspect  of  the  sixth  and  seventh  segments  and 
almost  a  rudimentary  sentus  on  the  eighth  segment  which  is  without  a 
pinaculum.  In  Epilachna  the  lateral  aspect  of  the  seventh  segment  is 
provided  with  a  distinct  parascolus  rather  than  with  a  scolus  as  in  the 
sixth;  while  the  eighth  segment  has  a  struma  and  the  ninth  only  a 
few  chalazae.  There  is  a  distinct  chalaza  surrounded  by  a  group  of  fine 
setae  ventrad  of  the  lateral  sentus  of  each  segment.  This  chalaza  and  the 
setae  represent  a  paralateral  group.  Each  sternum  is  as  wide  and  as 
long  as  its  respective  tergum.  The  cuticle  of  each  segment  is  soft  and 
bears  four  distinct  chalazae  arranged  in  a  transverse  row.  Each  chalaza 
is  surrounded  by  a  group  of  small  setae.  The  ventral  groups  are  adjacent 
to  the  ventro-meson  and  the  ventro-lateral  groups  are  located  near  the 
extreme  lateral  margin  of  each  segment.  The  coriae  between  the  seg- 
ments are  distinct. 

The  ninth  abdominal  segment  is  small,  cylindrical,  slightly  narrower 
and  shorter  than  the  eighth.  The  tergum  is  inclined  ventrad  at  an  angle 
of  about  thirty  degrees.  The  dorsal  senti  are  absent  and  in  their  place 
there  are  distinct  dorsal  strumae.  The  dorso-lateral  senti  are  also  reduced 
to  strumae  and  located  near  the  lateral  margin  of  the  tergum.  The  lateral 
aspect  is  small  and  the  senti  are  wanting,  but  there  is  a  prominent  chalaza 
surrounded  by  a  group  of  setae  near  the  ventral  margin.  This  group 
represents  the  lateral  group;  the  paralaterals  are  wanting.  The  ninth 
sternum  is  short,  deeply  emarginated  on  the  caudal  margin,  and  bears  four 
chalazae  arranged  in  a  transverse  row.  The  ventral  chalazae  are  located 
adjacent  to  each  other  and  the  ventro-meson  and  are  surrounded  by  a 
group  of  fine  setae;  while  the  ventro-lateral  are  without  setae.  Through- 
out the  family  the  ninth  segment  shows  the  greatest  variation  in  its  size, 
shape,  and  structure.  In  Chilocorus  the  ninth  abdominal  segment  is 
rectangular,  about  twice  as  wide  as  long;  its  anterior  margin  is  little  if  any 
narrower  than  the  eighth  segment;  the  caudal  margin  is  sharply  rounded 
and  never  serrated;  and  its  lateral  aspect  bears  chalazae  and  setae.  The 
lateral  aspect  of  the  ninth  segment  in  Epilachna  is  rectangular,  about 
twice  as  wide  as  long,  much  narrower  than  that  of  the  eighth  segment,  and 


2551  THE  LARVAE  OP  THE  COCCINELLIDAE— GAGE  •  23 

with  the  caudal  margin  broadly  rounded.  Each  lateral  aspect  bears  a 
small  chalaza.  In  all  of  the  genera  of  the  Coccinellini  the  ninth  segment 
is  more  or  less  rectangular.  The  caudal  margin  is  broadly  rounded,  usually 
widest  near  the  middle,  distinctly  narrower  than  the  eighth  segment,  and 
never  crenulate  or  serrate.  The  lateral  aspect  is  provided  with  numerous 
setae.  In  Microweisea  the  ninth  segment  is  conical,  about  twice  as  long 
as  wide,  and  much  narrower  than  the  eighth.  The  distal  margins  are 
sharply  rounded  and  the  tergum  is  chitinized  and  brown.  The  lateral 
aspect  is  provided  with  a  few  fine  setae.  In  Scymnus  the  ninth  segment 
is  conical,  about  one-half  as  wide  as  long,  much  narrower  than  the  eighth 
and  not  heavily  chitinized.  In  Hyperaspis  the  ninth  segment  is  semi- 
circular, about  twice  as  wide  as  long,  and  narrower  than  the  eighth.  The 
caudal  margin  is  broadly  rounded  and  never  crenulate  or  serrate.  The 
lateral  aspect  bears  a  few  fine  setae. 

The  tenth  abdominal  segment  is  as  a  rule  not  visible  from  the  dorsal 
aspect.  It  appears  to  be  a  small  ring  of  thin  membrane  surrounding  the 
rosetted  anal  area.  In  the  Coccinellini  this  membrane  is  often  pigmented 
and  appears  black  or  brown  colored.  The  rosetted  appearance  of  the  anal 
area  is  caused  by  the  evagination  of  the  rectum.  This  serves  as  a  sucking 
disk  and  aids  the  larvae  in  locomotion. 

In  all  the  coccinellid  larvae  there  are  eight  pairs  of  abdominal  spiracles 
(Figs.  1  and  2,  ahdsp),  a  pair  situated  on  each  abdominal  segment  from  one 
to  eight  inclusive.  They  are  located  near  the  cephalic  margin  of  each 
tergum  between  the  dorso-lateral  and  lateral  senti  in  Chilocorus  and  Anatis, 
between  the  dorso-lateral  and  lateral  scoli  in  Epilachna,  between  the  dorso- 
lateral and  lateral  parascoli,  strumae  or  verrucae  in  Hippodamia,  Coc- 
cinella,  Megilla,  Adalia,  and  Scymnus,  and  between  the  dorso-lateral  and 
lateral  chalazae  or  setae  in  Hyperaspis. 

There  is  a  pair  of  repugnatorial  pores  on  segments  one  to  eight  (Figs. 
1,  2,  rp).  These  pores  are  located  on  each  lateral  margin  of  the  tergum 
in  the  coria  between  the  segments.  They  emit  a  bad  smelling  fluid  which 
is  of  a  repulsive  nature  and  serves  to  protect  the  larva  from  its  enemies. 

On  each  side  of  the  dorso-meson  in  segments  one  to  eight  there  are  two 
small  pits.  There  is  another  pair  on  each  side  of  the  tergum  near  the  mid- 
dle about  midway  between  the  dorsal  and  dorso-lateral  senti  of  segments 
one  to  nine.  All  of  these  pits  are  arranged  in  a  transverse  row  on  the 
tergum.  There  is  another  pit  on  the  lateral  aspect  of  segments  one  to 
nine  which  is  located  immediately  ventrad  of  the  ventral  senti.  These 
pits  are  probably  the  points  of  attachment  for  muscles. 

ARMATURE  OF  THE  BODY-WALL 

The  armature  of  coccinellid  larvae  consists  of  spine-like  setae  on  the 
body- wall  or  of  conical,  finger-like,  or  mound-like  projections  of  the  body- 


24  ILLINOIS  BIOLOGICAL  MONOGRAPHS  ^S6 

wall  which  bear  setae.  They  are  known  as  scoli,  senti,  parascoli,  strumae, 
verrucae,  chalazae,  or  setae  and  vary  greatly  in  form  in  the  different 
tribes  and  genera  of  the  family.  After  a  study  of  the  larvae  of  the  Chry- 
somelidae,  the  probable  progenitors  of  the  Coccinellidae,  one  becomes 
convinced  that  Chelymorpha  shows  perhaps  the  greatest  resemblance  to 
the  generalized  coccinellids.  In  Chelymorpha  each  lateral  margin  of  the 
body  is  provided  with  a  longitudinal  row  of  long  branched  projections  of 
the  body-wall.  The  distal  end  of  each  of  these  branches  bears  a  stout  seta. 
Fracker  in  his  work  on  lepidopterous  larvae  called  structures  similar  to 
these  scoli.  It  was  unfortunate,  however,  when  he  applied  the  same  term 
to  a  non-branched  projection  of  the  body-wall  which  bears  setae  upon  its 
trunk.  These  two  structures  are  so  widely  different  that  they  cannot  be 
considered  as  one  and  the  same  thing  and  for  the  latter  the  name  sentus  is 
proposed.  Fracker  has  also  shown  that  the  arrangement  and  number  of 
setae  on  the  prothorax  represents  the  generalized  condition  in  lepidopterous 
larvae.  This  may  be  true  in  coccineUid  larvae,  but  there  has  been  no 
attempt  made  in  this  work  to  homologize  the  setae  or  the  projections  that 
bear  them.  Since  the  arrangement  of  the  setae  in  the  various  genera 
differs,  especially  on  the  abdominal  segments,  this  character  has  been 
used  to  some  extent  in  separating  genera,  and  it  is,  therefore,  necessary  to 
adapt  a  tentative  nomenclature  for  these  structures.  This  nomenclature 
is  based  upon  the  concKtions  found  in  the  third  abdominal  segment  and 
has  been  applied  only  to  the  segments  of  the  abdomen. 

There  is  a  seta  or  a  projection  bearing  a  seta  or  setae  on  each  side  of  the 
dorso-meson.  These  are  designated  as  the  dorsal  group.  The  projection 
on  each  lateral  margin  of  the  tergum  is  a  dorso-lateral  group,  the  one  on 
the  dorsal  portion  of  the  lateral  aspect  is  a  lateral  group,  the  one  on  the 
ventral  margin  of  the  lateral  aspect  is  the  paralateral  group,  the  small 
group  on  each  lateral  margin  of  the  sternum  is  a  ventro-lateral  group,  and 
the  one  on  each  side  of  the  ventro-meson  is  the  ventral  group. 

The  scolus  is  a  branched  projection  of  the  body-wall,  usually  more  than 
five  times  as  long  as  wide  (Fig.  28).  Each  branch  of  the  scolus  bears  at 
its  distal  end  a  single  stout  seta.  The  dorsal  and  lateral  surfaces  of  the 
thorax  and  abdomen  of  Epilachna  are  provided  with  distinct  scoli. 

The  parascolus  is  a  modification  of  the  scolus  in  which  the  projection 
is  not  more  than  three  times  as  long  as  wide  and  usually  not  more  than 
twice  (Fig.  30).  This  structure  bears  a  few  short  branches  which  are  about 
as  wide  as  long,  each  with  a  seta  at  its  distal  end.  This  modified  scolus  is 
designated  as  a  parascolus.  It  is  found  in  Hippodamia,  Coccinella,  and 
on  the  caudal  segments  of  Anatis. 

A  sentus  is  an  elongated,  cone-Uke  projection  of  the  body-wall  which 
is  not  branched  hke  a  scolus,  but  bears  a  few  short  stout  setae  upon  its 
trunk  (Fig.  29).     Fracker  called  this  a  scolus,  but  it  differs  decidedly  in 


257]  THE  LARVAE  OF  THE  COCCINELLIDAE—GAGE  25 

form  from  the  true  scolus  and  has  been  called  a  sentus.  Senti  are  found 
in  Chilocorous  and  Anatis.  In  the  latter  genus  the  senti  are 'short  and 
thick. 

A  pinaculum  is  the  more  or  less  chitinized  plate  which  surrounds  the 
base  of  a  scolus,  sentus,  or  parascolus  (Figs.  28,  29,  30).  It  usually  bears 
numerous,  small,  dark-colored  setae.  Several  pinacula  may  become  fused 
to  form  the  shield-like  plates  of  the  body. 

A  chalaza  is  a  distinct  but  slight  pimple-like  projection  of  the  body-wall. 
It  may  be  considerably  wider  than  long  and  bears  on  its  distal  end  a  stout 
seta  (Fig.  33).  Chalazae  are  present  in  practically  all  coccinellid  larvae. 
They  are  for  the  most  part  found  on  the  sternum  and  in  some  cases  on 
the  lateral  aspect.  In  Microweisea  distinct  chalazae  are  found  on  the 
dorsal  aspect  of  the  abdomen,  there  are  also  distinct  chalazae  on  the  dorsal 
shield  in  most  of  the  genera  of  the  family. 

A  struma  is  a  parascolus  which  has  become  shortened,  usually  appearing 
to  be  nothing  more  than  a  distinct  mound-like  projection  of  the  body-wall 
(Fig.  31)  upon  which  are  situated  a  few  chalazae.  This  structure  was  for- 
merly called  a  tubercule,  but  this  term  is  misleading  and  has  been  applied 
by  various  workers  to  most  any  kind  of  an  extension  of  the  body-wall. 
In  order  to  avoid  further  confusion  the  term  struma  is  proposed  for  this 
structure.  Strumae  are  found  in  the  armature  of  the  abdomen  of  Adalia 
and  Megilla. 

The  struma  becomes  much  reduced  in  some  of  the  more  specialized 
larvae  so  that  it  appears  to  be  mound-like  and  bears  setae  instead  of 
chalazae  (Fig.  32).  This  structure  has  also  been  called  a  tubercule  by 
some  workers  and  by  others  a  verruca.  Since  the  term  verruca  is  not 
misleading  or  conflicting,  it  should  be  restricted  to  structures  such  as  these. 
Verrucae  are  found  in  the  armature  of  Scymnus  and  very  small  indistinct 
ones  in  Microweisea;  the  latter  genus  also  bears  chalazae. 

In  the  most  specialized  of  the  coccinellids  verrucae  and  chalazae  have 
become  so  greatly  reduced  that  the  setae  are  not  elevated  above  the 
general  surface  of  the  body  (Fig.  34).  Setae  are  found  on  the  body  of  all 
of  the  more  generalized  coccinellids,  but  it  is  only  in  the  more  specialized 
groups  that  the  setae  constitute  the  only  type  of  armature.  The  Hyper- 
aspini  is  the  only  tribe  that  I  have  studied  which  has  this  condition. 

In  the  niore  generalized  genera  the  armature  of  the  body  consists  of 
scoli  arranged  upon  the  dorsal  and  lateral  surfaces.  Such  a  condition  as 
this  is  found  in  the  subfamily  Epilachninae.  In  Chilocorous  and  Anatis 
the  scoli  are  replaced  by  senti  on  the  dorsal  and  lateral  aspects  and  on  these 
regions  in  Hippodamia,  Coccinella,  and  to  a  small  extent  in  Adalia  para- 
scoli  are  present.  The  projections  of  Adalia  seem  to  show  a  stage  of 
transformation  between  parascoli  and  strumae;  for  parascoli  are  found  on 
the  dorsal  surface  and  strumae  on  the  lateral.     Strumae  are  found  on  the 


26  ILUNOJS  BIOLOGICAL  MONOGRAPHS  (258 

dorsal  and  lateral  regions  of  Megilla,  but  on  the  lateral  aspect  of  the  eighth 
segment  there  is  a  verruca.  Verrucae  are  found  almost  exclusively  on 
Scymnus,  while  in  Microweisea  they  are  very  small  and  closely  approxi- 
mate the  form  of  chalazae.  Verrucae  are  also  found  on  the  ventral  por- 
tion of  the  ninth  segment  in  practically  all  genera  of  the  Coccinellidae,  the 
only  exceptions  being  Hyperaspis  and  Scymnus.  Chalazae  are  found  on 
the  dorsal  shield  and  on  the  shield-like  spots  of  the  mesothorax  and  meta- 
thorax  of  Hippodamia,  Megilla,  Anatis,  Adalia,  and  Coccinella.  There  are 
also  a  few  on  the  prothoracic  shield  of  Scymnus.  The  same  type  of  arma- 
ture is  present  on  the  ventral  parts  of  the  thoracic  and  abdominal  seg- 
ments throughout  the  family  and  on  the  lateral  portions  of  the  eighth  and 
ninth  segments  of  Adalia,  Megilla,  and  Scymnus.  They  are  usually  sur- 
rounded by  a  group  of  finer  setae.  In  Hyperaspis  and  its  allies  the  arma- 
ture of  the  body  has  been  so  reduced  that  it  is  composed  of  setae  forming  a 
hair-like  covering  over  the  entire  surface.  The  ventral  surface  of  all  of  the 
members  of  the  family  is  provided  with  setae  rather  than  scoli,  parascoli, 
senti  or  strumae.  Even  in  those  genera  where  chalazae  or  verrucae  are 
found  on  the  ventral  surface,  setae  are  also  abundant.  The  type  of  arma- 
ture of  the  Coccinellidae  shows  a  steady  and  unbroken  series  of  changes  in 
specialization  from  the  generalized  scolus  to  a  seta  through  the  reduction 
or  the  disappearance  of  parts. 


259]  THE  LARVAE  OF  THE  COCCINELLIDAE—GAGE  27 


SYNOPSIS  OF  LARVAE 

In  the  taxonomic  study  of  any  group  of  organisms,  the  investigator 
should  not  draw  conclusions  from  characteristics  which  upon  the  surface 
may  show  a  high  degree  of  specialization  or  generalization,  without  first 
making  a  careful  study  of  these  characteristics,  no  matter  how  important 
or  unimportant  they  may  seem.  According  to  Comstock,  "The  logical 
way  to  go  to  work  to  determine  the  affinities  of  the  members  of  a  group  of 
organisms  is  first  to  endeavor  to  ascertain  the  structure  of  the  primitive 
members  of  this  group;  and  then  endeavor  to  ascertain  in  what  ways  these 
primitive  forms  have  been  modified  by  natural  selection."  With  such  a 
view  as  this  in  mind,  the  taxonomist  must  not  only  study  the  members  of 
the  group  upon  which  he  is  working,  but  he  must  also  endeavor  to  ascertain 
the  conditions  that  existed  in  the  progenitors  of  the  group.  It  is  obvious, 
then,  that  those  conditions  in  the  chosen  group  which  are  most  nearly 
similar  to  the  conditions  in  their  progenitors  are  the  most  generalized; 
further,  that  those  individuals  possessing  these  primitive  characteristics 
are  the  generalized  individuals  of  the  group.  There  are  often  two  or  more 
sets  of  prominent  characters,  and  many  times  these  may  not  run  in  parallel 
lines,  but  seem  to  contradict  each  other  or  to  run  in  opposite  directions. 
For  instance  in  the  larvae  of  the  Coccinellidae  that  form  which  shows  the 
most  generalized  condition  of  the  head  sutures,  the  Epilachninae,  have 
also  what  seems  to  be  the  most  highly  specialized  condition  of  the  setae 
or  scoli  on  the  body;  and  Hyperaspini  which  have  the  most  highly  special- 
ized condition  of  the  head  sutures  show  what  appears  to  be  the  most 
generalized  condition  of  the  setae. 

If  one  studies  the  conditions  present  in  the  Chrysomelidae,  the  prob- 
able progenitors  of  the  Coccinellidae,  he  will  find  in  the  genus  Chelymorpha 
conditions  of  the  epicranial  suture  and  scoli  similar  to  those  found  in  the 
Epilachnini.  The  epicranial  stem  in  Chelymorpha  is  long  and  the  epi- 
cranial arms  are  gradually  divergent,  a  condition  almost  identical  with 
that  of  the  Epilachninae.  The  members  of  the  subfamily  Coccinellinae 
have  a  much  shorter  epicranial  stem  or  in  many  genera  it  may  be  entirely 
wanting  and  the  epicranial  arms  diverge  immediately  from  the  occipital 
foramen.  Even  the  epicranial  arms  are  wanting  in  the  adult  larvae  of 
Scymnus  and  H)rperaspini;  while  the  clypeal  suture,  which  is  distinct  and 
entire  in  Chelymorpha  and  Epilachna,  is  incomplete  and  only  indicated 


28  ILLINOIS  BIOLOGICAL  MONOGRAPHS  [260 

on  each  margin  of  the  head  in  the  Coccinellinae.  This  fact  tends  to  show 
a  complete  reduction  of  the  sutures  which  are  distinct  in  Epilachna  and 
are  entirely  wanting  or  only  slightly  indicated  in  the  Hyperaspini. 

The  condition  of  the  armature  of  the  body  also  shows  a  like  reduction. 
In  both  Epilachna  and  Chelymorpha  scoli  are  present.  In  Chilocorus  the 
scoli  are  replaced  by  senti  and  in  those  forms  which  show  a  further  reduc- 
tion of  the  epicranial  arms  we  find  that  there  is  a  further  reduction  in  the 
armature  of  the  body.  In  Hippodamia,  Coccinella,  Adalia,  Anatis,  and 
Microweisea,  forms  in  which  the  epicranial  arms  alone  are  present,  the 
armature  consists  of  parascoli,  strumae,  verrucae,  and  chalazae  or  setae; 
while  in  the  Hyperaspini  in  which  the  epicranial  suture  is  wanting  the  body 
is  provided  only  with  setae.  The  condition  of  the  scoli  in  Epilachna  might 
easily  be  taken  as  a  highly  specialized  characteristic,  but  when  one  studies 
the  characteristics  of  the  progenitors  of  the  CoccineUidae,  he  finds  such  a 
condition  in  the  armature  of  the  body  as  is  found  in  the  Epilachninae. 
There  is  a  further  likeness  between  the  Chrysomelidae  and  the  Epilach- 
ninae that  seems  also  to  be  of  importance,  that  is  the  food  habits  of  the 
two  are  almost  identical,  as 'both  are  phytophagous.  The  Epilachninae 
are  perhaps  the  only  group  of  coccinellids  that  are  entirely  phytophagous 
in  both  the  larval  and  adult  stages. 

The  fact  that  the  setae  in  Hyperaspini  show  an  apparently  generalized 
condition,  while  the  epicranial  suture  is  absent  in  the  adult  larval  stages 
and  present  in  the  first  larval  stages,  surely  a  specialized  condition,  does 
not  interfere  with  this  proposed  classification.  For  specialization,  as 
Comstock  has  pointed  out,  may  take  place  in  two  wholly  different  ways. 
"First,  by  the  addition  or  complication  of  parts,  specialization  by  addition; 
second,  by  the  reduction  in  the  number  or  the  complexity  of  the  parts, 
specialization  by  reduction."  The  latter  is  considered  to  be  the  case  in 
the  Hj^eraspini;  the  primitive  scoli  have  been  reduced  to  setae.  Granting 
this  to  be  true,  we  can  readily  see  that  these  two  wholly  different  charac- 
teristics, the  condition  of  the  scoli  and  the  epicranial  suture,  show  in  a 
very  striking  way  the  presence  of  specialization  in  Hyperaspini  and  of 
generalization  in  the  Epilachninae.  In  the  first  case  there  is  the  absence 
of  the  epicranial  stem,  only  an  indication  of  the  clypeal  suture,  and  a 
reduction  of  the  scoli  to  setae;  while  in  the  latter  there  is  the  presence  of 
the  epicranial  and  clypeal  sutures  and  of  scoli  similar  in  form  to  those  of 
Chelymorpha. 

Since,  as  Comstock  has  shown,  there  is  such  a  thing  as  specialization 
by  reduction  and  since  the  progenitors  of  the  coccinellids,  as  nearly  as  we 
can  ascertain,  have  an  epicranial  and  a  clypeal  suture  and  a  well-developed 
system  of  scoli,  it  seems  to  me  altogether  logical,  and  with  the  evidence 
at  hand  quite  clear  that  the  Epilachninae  represent  a  generalized  type  of 
coccinellid  larvae,  though  at  a  first  glance  they  may  appear  to  be  highly 
specialized. 


261]  THE  LARVAE  OF  THE  COCCI NELLJ DAE— GAGE  29 

There  is  a  great  variation  in  the  general  structure  of  the  larvae  of  the 
Coccinellidae.  This  variation  ranges  from  the  phytophagous  type  found 
in  Epilachna  to  the  extreme  carnivorous  type  found  in  Scymnus  and 
Hyperaspis.  The  larvae  of  the  family  possessing  the  phytophagous  type 
of  structure  can  very  easily  be  mistaken  for  certain  chrysomelid  larvae 
which  they  resemble  in  general  shape  and  in  the  arrangement  of  their 
scoli  and  pinacula,  while  those  of  the  more  carnivorous  types  might  at 
first  glance  be  mistaken  for  chrysopid  larvae.  The  coccinellid  larvae  may 
be  distinguished  from  this  latter  group  by  the  development  of  the  mandi- 
bles which  are  not  so  prominent  in  the  coccinellids.  The  mandibles  of  all 
of  the  carnivorous  coccinellids  differ  from  those  of  the  Chrysomelidae  in 
that  they  are  not  so  broad  and  have  a  smaller  number  of  dentes;  while  in 
Epilachna  they  resemble  very  closely  the  chrysomelid  mandibles.  All 
of  the  coccinellid  larvae  examined  possess  three  ocelli  on  the  lateral  por- 
tions of  the  head,  while  the  chrysomelid  larvae  may  possess  from  one  to 
six  or  none  on  each  side. 

The  Epilachninae  are  undoubtedly  the  most  primitive  type  of  coc- 
cinellid larvae,  a  fact  which  is  shown  by  their  likeness  to  their  chrysomelid 
progenitors.  Among  the  carnivorous  coccinellids,  Chilocorus  is  the  most 
primitive,  while  Hyperaspis,  which  is  the  farthest  removed  from  the 
chrysomelid  larvae,  shows  the  most  specialized  condition. 

SUBFAMILIES  OF  COCCINELLIDAE 

Epicranial  suture  present,  epicranial  stem  extending  one-half  the  dis- 
tance from  the  occipital  foramen  to  a  line  drawn  through  the  anta- 
coriae;  clypeal  suture  present;  antennae  slender,  more  than  three 
times  as  long  as  wide;  body  with  scoli Epilachninae 

Epicranial  suture  present  or  wanting,  when  present,  the  epicranial  stem 
never  extending  one-half  the  distance  from  the  occipital  foramen  to 
a  line  drawn  through  the  antacoriae;  clypeal  suture  never  complete, 
only  indicated  on  each  side;  antennae  short,  never  more  than  twice 
as  long  as  wide;  body  without  scoli Coccinellinae 

EPILACHNINAE 

The  body  is  elongate,  oval  to  fusiform.  The  dorsal  and  lateral  aspects 
are  armed  with  scoli,  the  sternum  with  strumae  or  chalazae,  and  the  head 
with  a  few  long  setae.  The  epicranial  stem  and  epicranial  arms  are  always 
present;  the  clypeal  suture  is  entire  and  distinct.  The  antennae  are  more 
than  three  times  as  long  as  wide,  inserted  more  than  their  own  length 
dorso-mesad  of  the  precoila.  Each  mandible  is  heavily  chitinized,  its  mola 
not  well  developed,  and  the  distal  portion  with  several  dentes  of  various 
lengths,  the  distal  dentes  the  longest. 

This  subfamily  is  represented  in  North  America  by  a  single  tribe,  the 
Epilachnini.     Casey  says,  "This  tribe  is  represented  in  the  United  States 


30  ILUNOIS  BIOLOGICAL  MONOGRAPHS  [262 

by  two  or  three  large  pubescent  species  belonging  to  the  single  genus 
Epilachna."  One  species  occurs  in  small  numbers  in  southern  Illinois. 
The  Epilachninae  are  truly  phytophagous.  Our  common  species  feeds 
almost  entirely  upon  the  squash  plant  and  its  relatives.  The  beetle  is 
commonly  called  the  squash  lady-bug.  This  subfamily  is  represented  in 
the  material  studied  by  a  single  species  of  the  genus  Epilachna  Chevrolat. 
Epilachna  borealis  Fab. — The  prothorax  is  slightly  chitinized  with  a 
transverse  row  of  four  scoli  on  the  dorsum  near  its  cephalic  margin  and  a 
transverse  row  of  small  setae  on  its  caudal  margin;  the  pleural  area  is  small 
and  glabrous;  the  prosternum  is  short  with  two  distinct  setae  on  the 
ventro-meson;  and  the  procoxacoriae  are  distant.  The  mesothorax  and 
metathorax  are  subequal  in  length  and  width,  the  dorsum  of  each  with 
four  scoli,  two  on  each  side  of  the  meson  arising  from  the  same  pinaculum; 
the  mesothoracic  spiracles  are  located  in  the  mesocoria;  the  metathoracic 
spiracles  are  wanting;  the  caudal  portion  of  the  mesothoracic  and  meta- 
thoracic pleural  areas  are  each  provided  with  a  large  prominent  scolus; 
the  mesothoracic  and  metathoracic  sterna  are  each  provided  with  a  group 
of  setae  on  each  side  of  the  ventro-meson;  and  the  mesocoxacoriae  and 
metacoxacoriae  are  distant.  The  coxa  is  short  and  subcylindrical;  the 
trochanter  is  triangular,  about  as  long  as  the  coxa  and  bears  a  few  setae; 
the  femur  is  as  wide  as  the  trochanter,  about  twice  as  long  and  covered 
with  numerous  small  stiff  setae;  the  tibia  is  about  as  long  as  the  femur  and 
about  two-thirds  as  wide,  its  dorsal  and  lateral  surfaces  are  covered  with 
short  stiff  setae,  its  ventral  surface  is  thickly  covered  with  fine  setae,  and 
the  distal  one-third  is  covered  with  tenent  hairs;  and  the  tarsus  consists 
of  a  single  segment  which  bears  the  heavily  chitinized  hooked  claw  and 
a  few  tenent  hairs.  The  terga  of  the  abdominal  segments  one  to  eight 
inclusive  are  similar.  Each  tergum  is  provided  with  four  scoli,  the  dorsal 
scoli  are  adjacent  to  each  other  and  the  meson  and  the  dorso-lateral  scoli 
are  on  the  lateral  margins  of  the  tergum.  The  ninth  tergum  bears  four 
strumae  which  represent  the  dorsal  and  dorso-lateral  groups;  the  tenth 
segment  is  membraneous.  Each  lateral  aspect  of  segments  one  to  six  is 
provided  with  a  prominent  lateral  scolus,  of  segments  seven  and  eight  with 
a  lateral  struma,  and  of  segment  nine  with  a  lateral  verruca.  The  para- 
lateral  group  is  represented  by  a  prominent  chalaza  surrounded  by  a  group 
of  small  setae  ventrad  of  each  lateral  scolus.  Sternum  one  is  provided 
with  two  prominent  ventral  chalazae,  the  ventro-laterals  are  wanting; 
sterna  two  to  nine  bear  two  adjacent  ventral  chalazae  and  two  ventro- 
lateral chalazae  located  near  the  lateral  portion  of  each  sternum;  and 
sternum  ten  is  crescent-shaped  and  armed  with  setae.  The  rectum  is 
evaginated  to  form  a  disk-like  sucker.     It  is  used  as  an  aid  in  locomotion. 


263]  THE  LARVAE  OF  THE  COCCINELLIDAE—GAGE  31 

COCCINELLTNAE 

The  body  is  elongate  to  oval,  dorsal  surface  convex,  ventral  surface 
concave  or  flat.  The  body-wall  is  provided  with  senti,  strumae,  verrucae, 
chalazae,  or  evenly  distributed  setae.  The  head  is  provided  with  long 
distinct  setae.  The  epicranial  stem  and  epicranial  arms  may  be  present 
or  wanting,  when  present,  the  epicranial  stem  never  extends  more  than 
one-third  of  the  distance  from  the  occipital  foramen  to  a  line  drawn  through 
the  antacoriae.  The  clypeal  suture  is  never  entire,  but  is  usually  indicated 
by  a  distinct  furrow  which  extends  mesad  on  each  side  from  the  precoila. 
The  antennae  are  never  more  than  three  times  as  long  as  wide,  consist 
of  three  segments,  and  are  inserted  about  midway  between  the  ocelli  and 
the  precoilae.  The  mandibles  usually  have  one,  two,  or  three  teeth  at  the 
distal  end,  and  the  proximo-mesal  margin  is  provided  with  a  triangular  or 
mound-shaped  mola. 

This  subfamily  includes  all  of  those  tribes  the  members  of  which  are 
carnivorous.  They  may  also  be  phytophagous  to  the  extent  that  they 
may  eat  fungi  and  probably  small  amounts  of  pollen. 

Tribes  of  Coccinellinae 

1(6)  Epicranial  arms  always  present;  epicranial  stem  always  present 
in  all  larval  stages  unless  obliterated  by  the  separation  of  the 
epicranial  arms 2 

2(3)  The  dorsum  of  the  body  armed  with  senti  six  to  eight  times  as  long 
as  wide;  the  epicranial  stem  extending  one-third  of  the  distance 
from  the  occipital  foramen  to  a  line  drawn  through  the  antacor- 
iae;   epicranial    arms    gradually    divergent Chilocorini 

3(2)  The  dorsum  of  the  body  never  armed  with  senti  six  to  eight  times 
as  long  as  wide 4 

4(5)  Dorsum  of  the  body  armed  with  short  senti,  parascoli,  or  strumae; 
epicranial  stem,  when  present,  never  extending  one-third  the 
distance  from  the  occipital  foramen  to  a  line  drawn  through  the 
antacoriae;  epicranial  arms  gradually  or  abruptly  divergent 
Coccinellini 

5(4)  Dorsum  of  the  body  provided  with  small  verrucae  or  setae;  epi- 
cranial stem  always  obliterated  by  the  separation  of  the  epicra- 
nial arms,  epicranial  arms  diverge  from  the  occipital  foramen 
Microiveiseini 

6(1)  Epicranial  stem  and  epicranial  arms  never  present  in  adult  larvae  7 

7(8)  The  dorsal  and  lateral  aspects  of  the  body  with  strumae  or 
verrucae Scymnini 

8(7)  The  dorsal  and  lateral  aspects  of  the  body  with  fine  slender  setae 
Hyperaspini 


32  ILLINOIS  BIOLOGICAL  MONOGRAPHS  [264 

Chilocorini 

The  body  is  subovate,  widest  at  the  metathorax.  The  first  three 
abdominal  segments  are  slightly  narrower  than  the  metathorax,  segments 
four  to  eight  are  successively  narrower,  segment  nine  is  about  as  wide  as 
long,  its  caudal  margin  is  broadly  rounded  and  its  lateral  margin  is  pro- 
vided with  a  distinct  struma;  and  segment  ten  is  small  and  directed  ven- 
trad.  The  dorsal  and  lateral  aspects  of  the  body  are  provided  with  long 
senti  the  length  of  which  varies  on  the  different  portions.  The  epicranial 
stem  and  epicranial  arms  are  present.  The  epicranial  stem  extends  about 
one-third  of  the  distance  from  the  occipital  foramen  to  a  line  drawn  through 
the  antacoriae,  divides  and  forms  the  two  epicranial  arms  which  diverge 
gradually  for  a  short  distance,  then  widely,  and  finally  each  extends 
laterad  to  a  point  dorsad  of  an  antacoria  and  ventrad  of  an  ocellus  where 
it  becomes  obsolete.  The  mandibles  are  triangular  in  outline,  heavily 
chitinized,  the  apex  is  bifurcated,  and  the  proximo-mesal  margin  is  pro- 
vided with  a  distinct  mola. 

This  tribe  is  represented  in  the  material  studied  by  the  single  genus 
Chilocorus  Leach. 

Chilocorus  bivulnerus  Muls. — The  head  is  chitinized,  dark,  and  pro- 
vided with  numerous  setae.  The  epicranial  stem  and  epicranial  arms  are 
distinct;  the  clypeal  suture  is  indicated  on  each  lateral  margin  of  the  head. 
The  mouth  is  directed  cephalo-ventrad.  The  prothorax  is  provided  with 
a  large  dark  colored  dorsal  shield  bearing  ten  senti,  six  of  which  are  ar- 
ranged in  a  transverse  row  near  the  cephalic  margin.  The  lateral  aspect 
of  the  prothorax  bears  a  small  group  of  setae  cephalo-dorsad  of  the  pro- 
coxacoria.  The  cephalic  portion  of  the  prosternum  also  bears  a  small 
group  of  setae  on  each  side  of  the  meson.  The  procoxacoriae  are  distant. 
The  mesotergum  is  distinctly  longer  and  narrower  than  the  metatergum. 
Each  is  provided  with  four  large  senti  arranged  in  a  transverse  row;  the 
dorsal  senti  are  distinctly  smaller  than  the  lateral  ones.  The  pinacula  are 
small  and  bear  distinct  setae.  The  mesopleural  area  is  longer  than  the 
metapleural;  both  areas  are  obliquely  crossed  by  a  distinct  furrow.  The 
cephalic  portions  of  the  mesopleural  and  metapleural  areas  are  subequal 
in  size,  triangular,  and  each  provided  with  a  large  sentus.  The  meso- 
thoracic  spiracle  is  located  in  the  mesocoria  near  the  cephalic  margin  of  the 
mesothoracic  sentus;  the  metathoracic  spiracle  is  rudimentary  or  wanting. 
The  caudal  portions  of  the  mesopleural  and  metapleural  areas  are  unequal 
in  size,  that  of  the  metapleural  area  is  much  larger  than  that  of  the  meso- 
pleural. The  cephalic  metapleural  sentus  is  about  one-half  as  long  as  the 
caudal  one.  The  mesosternum  and  metasternum  are  similar  in  size  and 
shape.  The  mesocoria  is  distinct  while  the  metacoria  is  obscure.  The 
cephalic  portions  of  the  mesosternum  and  metasternum  are  each  provided 
with  a  chalaza  on  each  side  of  the  ventro-meson;  these  chalazae  are  sur- 


265]  THE  LARVAE  OF  THE  COCCINELLIDAE—GAGE  33 

rounded  by  groups  of  setae.     The  legs  are  about  as  long  as  the  body  is 
wide  and  the  tibia  is  very  densely  setaceous. 

The  first  abdominal  segment  is  shorter  than  the  metathorax  and  its 
tergum  bears  four  senti  arranged  in  a  transverse  row;  the  dorsal  pinacula 
are  yellow  and  the  dorso-lateral  ones  are  white;  the  lateral  aspect  is  rect- 
angular with  a  large  lateral  sentus  the  pinaculum  of  which  covers  the 
greater  part  of  the  lateral  surface  and  the  paralaterals  are  wanting.  The 
sternum  is  about  as  long  as  the  tergum,  the  ventral  setae  are  adjacent  on 
the  ventro-meson  while  the  ventro-laterals  are  wanting.  Abdominal  seg- 
ments two  to  five  are  similar,  narrower  than  the  first;  their  terga  are  sub- 
equal  in  length,  the  dorsal  and  dorso-lateral  senti  of  each  segment  are 
arranged  in  a  transverse  row,  and  each  sentus  is  provided  with  a  distinct 
pinaculum.  The  lateral  aspect  is  nearly  square;  the  lateral  senti  are 
larger  than  the  dorso-lateral,  their  pinacula  are  small.  Ventrad  of  the 
second  and  third  lateral  senti,  there  is  a  small  paralateral  seta  and  ventrad 
of  the  fourth  and  fifth  lateral  senti,  there  is  a  paraleteral  group  of  setae  sur- 
rounding a  distinct  paralateral  chalaza  on  each  segment.  The  sterna  are 
as  long  as  their  respective  terga,  slightly  chitinized,  their  coriae  are  dis- 
tinct, and  each  bears  four  chalazae  arranged  in  a  transverse  row,  each 
chalaza  surrounded  by  six  or  eight  small  setae.  Segments  six,  seven,  and 
eight  are  each  narrower  than  the  preceding  ones.  Their  dorsal  pinacula 
are  fused  and  the  dorso-lateral  senti  are  shorter  than  the  dorso-lateral  senti 
of  segments  two  to  five.  Their  lateral  aspects  are  smaller,  but  are  similar 
in  shape  to  those  of  the  preceding  segments,  the  lateral  aspects  of  the 
sixth  and  seventh  segments  are  provided  with  small  lateral  senti,  while  the 
lateral  sentus  of  the  eighth  segment  is  much  reduced  and  the  pinaculum 
is  absent.  Ventrad  of  each  lateral  sentus,  there  is  a  paralateral  chalaza 
surrounded  by  a  group  of  setae.  The  sterna  are  as  wide  as  the  terga,  their 
coriae  are  distinct,  and  the  ventral  and  ventro-lateral  groups  of  setae  sur- 
rounding the  chalazae  are  present.  The  ninth  abdominal  segment  is 
about  as  wide  and  about  as  long  as  the  eighth,  cylindrical,  and  inclined 
ventrad.  Its  tergum  is  shield-shaped  and  has  two  distinct  dorsal  verrucae 
near  the  caudo-mesal  margin,  the  dorso-lateral  verrucae  are  wanting.  Its 
lateral  aspect  is  small,  each  with  a  distinct  lateral  verruca,  ventrad  of  the 
verruca  there  is  a  distinct  paralateral  chalaza  surrounded  by  a  group  of 
setae.  Its  sternum  is  short,  deeply  emarginated  on  the  caudal  margin, 
the  ventral  and  ventro-lateral  groups  of  chalazae  are  present,  and  the 
ventral  chalazae  are  surrounded  by  a  few  setae  while  the  ventro-laterals 
are  represented  by  a  single  chalaza.  The  tenth  segment  is  small,  not 
visible  from  the  dorsal  aspect  and  the  rectum  is  evaginated  to  form  a  disk- 
like sucker.  There  is  a  pair  of  repugnatorial  pores  located  in  the  coriae  of 
segments  one  to  seven  about  one-half  the  distance  between  the  dorsal  and 
dorso-lateral  senti. 


34  ILUNOIS  BIOLOGICAL  MONOGRAPHS  [266 

Coccinellini 

The  body  is  fusiform  or  elongate,  widest  at  the  metathorax,  usually 
highly  colored  with  black,  red,  yellow,  orange,  or  blue;  never  with  senti 
except  in  Anatis  in  which  the  senti  are  short  and  thick,  but  never  five 
times  as  long  as  wide,  usually  with  parascoli  or  strumae.  The  abdomen 
becomes  gradually  narrower  toward  the  caudal  end.  The  ninth  abdominal 
segment  is  about  twice  as  long  as  wide,  never  wider  than  long  as  in  Chiloc- 
orini  or  Hyperaspini,  never  with  lateral  parascoli  or  strumae  as  in  Chiloc- 
orini,  dorsum  provided  with  a  light  colored,  slightly  chitinized  shield 
bearing  many  setae  or  chalazae.  The  head  is  heavily  chitinized,  the 
epicranial  stem,  if  present,  never  extends  one-third  the  distance  from  the 
occipital  foramen  to  a  line  drawn  through  the  antacoriae;  the  epicranial 
arms  are  usually  widely  divergent.    The  mouth  is  directed  cephalo-ventrad. 

The  members  of  this  tribe  are  more  numerous  in  Illinois  than  those 
of  any  of  the  other  tribes.  They  are  almost  wholly  carnivorous,  their 
only  plant  food  being  either  fungi  or  in  some  cases  pollen  grains. 

Genera  of  Coccinellini 

1(2)  Epicranial  stem  and  epicranial  arms  always  present;  terga  one  to 
eight  with  strumae  usually  bearing  three  distinct  chalazae  and 
densely  covered  with  fine  setae MegUla 

2(1)  Epicranial  arms  always  present;  epicranial  stem  obliterated  by  the 
separation  of  the  epicranial  arms 3 

3(4)  Terga  one  to  eight  with  senti,  not  five  times  as  long  as  wide  .Anatis 

4(3)  Terga  one  to  eight  without  senti 5 

5(8)  Terga  one  to  eight  with  parascoli  or  strumae  which  bear  more  than 
five  chalazae  and  are  sparsely  setaceous 6 

6(7)  Tarsal  claw  with  a  distinct  appendiculated  tooth  at  its  proximal 
end Coccinella 

7(6)  Tarsal  claw  without  a  distinct  appendiculated  tooth  at  its  proxi- 
mal end Hippodamia 

8(5)  Terga  one  to  eight  with  strumae  which  never  bear  more  than  five 
prominent  chalazae  and  the  surface  of  the  strumae  densely  seta- 
ceous  Adalia 

Megilla  Mulsant 

This  genus  is  represented  in  the  material  studied  by  a  single  species. 

Megilla  maculata  DeGeer. — The  body  is  elongate,  widest  at  the  meso- 
thorax  and  metathorax.  Its  general  color  is  black  and  mottled  with  light 
yellow  or  cream-colored  areas.  The  head  is  heavily  chitinized,  the  dorsal 
portion  dark  and  the  ventral  portion  more  or  less  white.  The  epicranial 
stem  is  present  as  a  short  line  or  suture  on  the  dorsal  portion  of  the  head. 
It  extends  about  one-fifth  of  the  distance  from  the  occipital  foramen  to  a 


2671  THE  LARVAE  OF  THE  COCCI NELLI DAE— GAGE  35 

line  drawn  through  the  antacoriae.  The  epicranial  arms  diverge  laterad 
and  ventrad  and  become  obsolete  slightly  mesad  of  the  antacoria.  The 
mouth  is  directed  ventrad.  The  cephalic  margin  of  the  prothoracic  shield 
is  provided  with  two  small  cream-colored  spots,  and  the  caudal  margin 
with  a  yellow  boundary.  The  mesothorax  and  metathorax  have  a  shield- 
shaped  cream-colored  area  on  the  dorso-meson;  the  cephalic  portion  of  the 
mesothoracic  and  metathoracic  lateral  aspects  are  also  cream-colored. 
There  is  a  light  colored  area  on  the  dorso-lateral  portions  of  abdominal 
segments  one  to  eight.  On  the  lateral  portion  of  the  first  segment,  and 
on  the  tergum  and  lateral  aspects  of  the  fourth  and  fifth  segments,  the 
cuticle  is  yellow.  The  ventral  aspect  of  the  entire  larvae  is  tan  colored. 
The  prothoracic  shield  is  provided  with  many  chalazae  and  numerous 
setae,  the  terga  of  the  mesothorax  and  metathorax  are  provided  with  a 
large  struma-like  shield  which  bears  six  to  eight  chalazae.  The  lateral 
aspect  of  the  prothorax  is  glabrous.  The  mesothoracic  spiracles  are 
situated  in  the  mesocoria  near  the  cephalic  margin  of  the  lateral  aspect 
and  each  spiracle  is  surrounded  by  three  or  four  small,  black  setae.  The 
cephalic  portion  of  the  lateral  aspect  of  the  metathorax  has  three  or  four 
setae,  but  the  metathoracic  spiracles  are  wanting.  The  caudal  portions 
of  the  mesothorax  and  metathorax  are  about  twice  as  large  as  the  cephalic 
and  provided  with  a  struma-like  plate  which  bears  six  to  eight  chalazae. 
The  sternum  of  all  of  the  thoracic  segments  is  provided  with  a  small  pair 
of  verrucae  adjacent  the  meson  near  the  cephalic  margin  of  the  segment. 
Each  tergum  of  segments  one  to  eight  is  provided  with  a  transverse  row  of 
four  strumae,  two  dorsal  and  two  dorso-laterals.  Each  struma  usually 
bears  three  distinct  chalazae.  The  lateral  aspect  of  segments  one  to  eight 
is  each  provided  with  a  large  lateral  struma  with  four  to  eight  chalazae, 
of  segments  two  to  eight  with  a  small  mound-like  paralateral  struma  usually 
with  one  large  chalaza  and  many  seta  on  each  segment.  Each  sternum  of 
segments  one  to  eight  has  a  transverse  row  of  four  chalazae,  each  chalaza 
surrounded  by  a  few  setae.  The  ventro-lateral  group  is  wanting  on  the 
first  sternum.  The  tergum  of  the  ninth  segment  is  longer  than  wide, 
shield-shaped,  its  cephalic  margin  slightly  emarginated,  darkly  colored 
and  densely  setaceous.  The  lateral  aspect  is  much  reduced  and  bears  a 
single  large  lateral  chalaza,  the  paralaterals  are  wanting.  The  sternum 
is  shorter  than  the  tergum,  the  caudal  margin  deeply  emarginate  with  the 
ventral  and  ventro-lateral  chalazae  distinct.  The  tenth  segment  is  not 
visible  from  the  dorsal  aspect,  slightly  setaceous,  and  appears  to  be  cylin- 
drical when  viewed  from  the  ventral  aspect.  The  legs  are  long  and  slender, 
about  one  and  one-half  times  as  long  as  their  thoracic  segment  is  wide. 

Anatis  Mulsant 

This  genus  is  represented  in  my  material  by  a  single  species. 

Anatis  15 -punctata  Oliv. — The  body  is  elongate,  widest  at  the  meta- 


36  ILLINOIS  BIOLOGICAL  MONOGRAPHS  [268 

thorax.  The  dorsal  portion  of  the  head  is  dark  colored  while  the  ventral 
part  of  the  face  is  white  or  yellow.  The  epicranial  stem  is  absent,  the 
epicranial  arms  extend  cephalad  and  ventrad  from  the  occipital  foramen 
for  a  short  distance  and  diverge  widely  laterad  and  ventrad;  they  become 
obsolete  dorso-mesad  of  the  antacoriae.  The  mouth  is  directed  cephalo- 
ventrad.  The  mesothorax,  metathorax,  and  the  first  eight  abdominal 
segments  bear  short  stout  senti  from  one  to  five  times  as  long  as  wide. 
The  prothorax  has  a  distinct  parascoli  on  the  caudo-lateral  margin  of  the 
dorsal  shield.  There  are  four  or  five  chalazae  cephalad  of  this  parascoli. 
The  caudo-mesal  portion  of  the  dorsal  shield  is  provided  with  a  distinct 
yellow  or  white  shield-shaped  area,  the  cephalic  portion  of  which  bears  two 
chalazae  adjacent  to  the  meson.  The  mesal  and  lateral  tergal  senti  of  the 
mesothorax  and  metathorax  arise  from  the  dorsal  shields  of  their  respec- 
tive segments.  The  caudal  portions  of  the  lateral  aspects  of  the  meso- 
thorax and  metathorax  are  each  provided  with  a  small  sentus.  The  meso- 
thoracic  spiracles  are  located  in  the  mesocoria  and  the  metathoracic  spiracles 
are  rudimentary  or  wanting.  The  thoracic  sterna  are  all  similar,  the 
sternum  of  each  segment  has  a  pair  of  small  verrucae  adjacent  to  each  other 
and  the  ventro-meson,  the  coxacoriae  are  distant.  The  first  to  eighth 
segments  of  the  abdomen  are  subequal  in  length.  Their  terga  are  pro- 
vided with  four  senti  arranged  in  a  transverse  row;  the  dorsal  senti  of  the 
sixth,  seventh,  and  eighth  segments  have  their  pinacula  fused  on  each 
segment,  and  the  dorso-lateral  senti  of  the  seventh  and  eighth  segments  are 
short  and  inconspicuous.  The  metathorax  and  the  first  abdominal  seg- 
ment are  each  provided  with  a  small  cream-colored  area  caudad  of  and 
about  one-half  the  distance  between  the  dorsal  and  dorso-lateral  senti. 
The  lateral  aspects  of  the  first  and  second  abdominal  segments  are  white, 
each  with  a  distinct  white  lateral  sentus  and  pinaculum;  the  lateral 
aspects  of  the  third  to  eighth  segments  are  cream-colored  with  their  senti 
and  pinacula  brown;  the  lateral  aspects  of  the  seventh  and  eighth  segments 
are  without  lateral  senti  but  are  provided  with  lateral  verrucae  while 
ventrad  of  each  lateral  sentus  or  verruca,  except  in  the  first,  ninth,  and 
tenth  segments,  there  is  a  distinct  chalaza  surrounded  by  a  few  setae  which 
represent  the  paralateral  group.  The  sterna  of  the  first  to  the  eighth 
segments  are  similar  in  shape,  except  that  they  become  narrower  toward 
the  caudal  extremity.  The  first  sternum  has  two  ventral  ohalazae  adjacent 
to  the  meson,  the  ventro-laterals  are  wanting,  while  in  sterna  two  to  eight 
the  ventral  and  ventro-lateral  groups  are  present  on  each  segment.  In  the 
eighth  and  ninth  segments  the  ventral  and  ventro-lateral  groups  on  each 
side  have  become  fused  so  that  there  appears  to  be  a  single  pair  on  each 
side  of  the  meson.  The  tergum  of  the  ninth  segment  is  longer  than  wide, 
shield-shaped,  and  with  many  setae  on  its  surface;  its  lateral  aspect  is  much 
reduced  and  bears  small  and  indistinct  lateral  verruca,  the  paralaterals 


269]  THE  LARVAE  OF  THE  COCCINELLJDAE—GAGE  37 

are  wanting;  and  its  sternum  is  provided  with  ventral  and  ventro-lateral 
chalazae.  The  tenth  tergum  is  not  visible  from  the  dorsal  aspect  and  the 
greater  part  of  its  ventral  aspect  is  hidden  by  the  evaginated  rectal  disk. 
The  legs  are  long  and  slender,  about  one  and  one-half  times  as  long  as  the 
metathorax  is  wide. 

CocciNELLA  Linne 
The  body  is  fusiform,  elongate  and  widest  at  the  metathorax.  The 
head  is  usually  light-brown  colored  and  provided  with  many  setae.  The 
epicranial  arms  diverge  immediately  from  the  occipital  foramen  and  be- 
come obsolete  near  the  antacoriae.  The  mouth  is  directed  ventrad  and 
slightly  cephalad.  The  thoracic  segments  are  provided  with  a  dorsal 
shield.  The  dorsal  and  dorso-lateral  aspects  of  abdominal  segments  one 
to  eight  are  provided  with  parascoli  or  verrucae,  the  ventro-lateral  aspect 
with  verrucae,  and  the  ventral  aspect  with  verrucae  or  chalazae  surrounded 
by  a  few  setae.  The  dorsum  of  the  ninth  abdominal  segment  is  shield- 
shaped  and  densely  setaceous,  the  ventral  aspect  is  provided  with  verrucae 
or  chalazae,  and  is  about  one-half  as  long  as  the  dorsal  aspect.  The  legs 
are  well  developed,  stout,  and  extend  beyond  the  lateral  margins  of  the 
body.  The  coxacoriae  are  distant.  The  basal  portion  of  the  tarsal  daw 
is  provided  with  a  distinct  appendiculate  tooth. 

Species  of  Coccinella 

Terga  one  to  eight  with  distinct  parascoli;  prothoracic  shield  with  two 
distinct,  longitudinal,  dark,  heavily  chitinized  areas  on  each  side  of 
the   meson C.   9-notata 

Terga  one  to  eight  with  strumae;  prothoracic  shield  with  a  single,  dark, 
heavily  chitinized  area  on  each  side  of  the  meson C.  sanguinea 

Coccinella  9-notata  Herbst. — The  body  is  fusiform,  usually  stout,  and 
widest  at  the  metathorax.  The  dorsal  and  dorso-lateral  surfaces  are  pro- 
vided with  parascoli,  and  the  ventro-lateral  surface  with  small  verrucae. 
The  general  color  is  light  grayish-brown  to  dark  tan  or  brown  marked  with 
white  or  lemon-yellow  areas.  The  dorsal  portion  of  the  head  is  light- 
brown  and  the  face  is  cream-colored.  The  epicranial  arms  diverge  from 
the  occipital  foramen  and  the  mouth  is  directed  slightly  ventrad  and 
cephalad.  The  prothorax  is  wider  than  long  and  oval  in  outline;  the  dorsal 
shield  covers  the  greater  part  of  its  dorsal  surface  and  bears  four  distinct, 
dark-colored,  longitudinal  areas;  and  the  cephalic,  lateral,  and  part  of  the 
caudal  margins  are  provided  with  chalazae.  The  mesothorax  and  meta- 
thorax are  subequal  in  size,  each  is  about  twice  as  wide  as  long  and  each 
dorsal  surface  is  provided  with  a  small  oval  dorsal  shield  on  each  side  of  the 
meson.  There  is  a  small  dorso-lateral  parascolus  on  the  caudo-lateral 
portion  of  both  the  mesothorax  and  metathorax.  Each  thoracic  sterna 
is  provided  with  a  pair  of  verrucae  which  are  adjacent  to  the  ventro-meson. 


38  ILUNOIS  BIOLOGICAL  MONOGRAPHS  [270 

The  dorsal  and  dorso-lateral  portions  of  abdominal  segments  one  to  eight 
are  provided  with  parascoli.  The  dorsal  parascoli  are  brown,  while  the 
dorso-lateral  and  lateral  ones  of  the  first  and  fourth  segment  are  white  or 
cream-colored,  and  also  the  area  near  the  pinacula  of  these  parascoli  is 
white.  Segments  two  to  nine  are  provided  with  paralateral  verrucae, 
while  segment  one  has  a  small  paralateral  chalaza.  The  sterna  of  segments 
two  to  nine  are  provided  with  four  verrucae  arranged  in  a  transverse  row 
on  each  sternum;  while  the  sternum  of  the  first  segment  has  only  two  ver- 
rucae, the  ventro-lateral  ones  are  absent.  The  ventral  and  ventro-lateral 
verrucae  on  either  side  of  the  meson  of  the  ninth  segment  are  almost  fused 
so  that  there  seems  to  be  only  two  on  this  segment.  The  dorsal  surface 
of  the  ninth  segment  is  about  twice  as  long  as  the  ventral,  shield-shaped, 
the  caudal  margin  is  rounded,  and  densely  setaceous.  The  legs  are  well 
developed,  long,  and  stout.  The  proximal  portion  of  the  ,tarsal  claw  is 
provided  with  a  distinct  appendiculate  tooth. 

Coccinella  sanguinea  Linn. — The  body  is  elongate  and  widest  at  the 
metathorax.  The  dorsal  and  lateral  surfaces  are  provided  with  strumae, 
and  the  ventral  surface  with  verrucae  or  chalazae.  The  general  color  of 
the  body  is  light  to  dark  brown,  mottled  or  spotted  with  yellow  or  cream- 
colored  areas.  The  head  is  light  brown  and  the  face  is  yellow.  The  mouth 
is  directed  ventrad  and  slightly  cephalad.  The  prothorax  is  about  three- 
fourths  as  long  as  wide,  and  the  caudal  margin  is  slightly  emarginated. 
The  dorsal  shield  is  light  brown  in  color,  entire,  with  a  light  yellow  line  on 
the  meson,  and  the  cephalic  and  lateral  margins  are  provided  with  chalazae. 
The  mesothorax  and  metathorax  are  subequal  in  size,  about  twice  as  wide 
as  long,  each  with  a  small  oval  shield  on  either  side  of  the  meson.  There 
is  a  light  yellow  area  on  the  meson  between  the  shields  of  each  segment. 
The  mesothoracic  spiracles  are  located  in  the  mesocoria  cephalo-dorsad 
of  the  mesocoxacoilae,  the  metathoracic  spiracles  are  rudimentary.  The 
caudal  portion  of  the  lateral  aspect  of  the  mesothorax  and  metathorax 
bears  a  small  verruca.  The  sterna  of  all  of  the  thoracic  segments  are 
provided  with  a  pair  of  small  verrucae  adjacent  to  each  other  and  the 
meson.  Abdominal  segments  one  to  eight  are  provided  with  dorsal  and 
dorso-lateral  strumae,  and  each  segment  bears  more  than  five  chalazae 
and  a  few  scattered  setae.  The  dorsal  strumae  of  the  fourth  abdominal 
segment,  the  dorso-lateral  strumae  of  the  first  and  fourth  segments,  and 
the  lateral  strumae  of  the  first,  fourth,  and  fifth  segments  are  white  or  light 
yeUow.  There  is  a  small  paralateral  struma,  which  in  many  cases  appears 
to  be  verruca-like,  located  ventrad  of  each  lateral  struma,  except  in  the 
first  abdominal  segment  where  it  is  wanting.  The  sterna  of  segments  one 
to  nine  are  each  provided  with  ventral  and  ventro-lateral  groups  of  chala- 
zae, except  in  the  first  segment,  where  the  ventro-lateral  groups  are 
wanting.     The  dorsum  of  the  ninth  segment  is  shield-shaped  with  the 


271]  THE  LARVAE  OF  THE  COCCINELLIDAE— GAGE  39 

caudal  margin  rounded,  is  twice  as  long  as  its  sternum,  is  dark  colored,  and 
bears  many  short  setae.  The  legs  are  long,  slender,  well  developed,  and 
the  tarsal  claw  is  provided  with  a  distinct  appendiculate  tooth  at  its 
proximal  end. 

HippoDAMiA  Mulsant 

The  body  is  fusiform,  elongate,  and  usually  widest  at  the  metathorax. 
The  head  is  brown  to  dark  colored  and  distinctly  setaceous.  The  epi- 
cranial arms  diverge  immediately  from  the  occipital  foramen  and  become 
obsolete  near  the  antacoriae.  The  mouth  is  directed  ventrad  and  slightly 
cephalad.  The  dorsum  of  each  thoracic  segment  is  provided  with  dis- 
tinctly chitinized  shield-shaped  areas  which  constitute  the  dorsal  shields. 
The  dorsal  and  dorso-lateral  aspects  of  the  body  are  provided  with  para- 
scoli.  The  tergum  of  the  ninth  abdominal  segment  is  shield-shaped, 
setaceous,  and  with  the  caudal  margin  broadly  rounded.  The  ventro- 
lateral aspect  of  the  body  is  provided  with  small  strumae;  while  the  sterna 
are  all  provided  with  verrucae.  The  legs  are  well  developed,  extend  beyond 
the  sides  of  the  body,  stout,  and  with  the  tarsal  claw  not  provided  with  a 
distinct  appendiculate  tooth  at  its  proximal  end.  The  coxacbriae  are 
distant. 

Species  of  Hippodamia 

Dorsal  shield  with  two  brown  or  black  chitinized  plates  on  each  side 
of  the  meson H.  convergens 

Dorsal  shield  with  a  single  brown  or  dark  chitinized  plate  on  each  side 
of  the  meson H.  13-punctata 

Hippodamia  convergens  Guer. — The  body  is  elongate,  widest  at  the 
metathorax,  and  the  dorsal  and  lateral  surfaces  are  provided  with  para- 
scoli.  The  general  color  of  the  body  is  dark-brown  to  black,  marked  with 
yellow,  orange,  red,  or  white.  The  head  is  dark-brown  to  black,  the  face 
is  lighter  than  the  dorsal  part.  The  epicranial  arms  diverge  immediately 
from  the  occipital  foramen  and  become  obsolete  dorso-mesad  of  the  anta- 
coriae. The  mouth  is  directed  ventrad-and  slightly  cephalad.  The  pro- 
thorax,  when  viewed  from  above,  is  oval  in  outline  and  wider  than  long. 
The  dorsal  shield  is  provided  with  four  longitudinal  dark  colored  areas 
separated  by  white  or  orange  colored  bands.  The  cephalic  and  lateral 
margins  of  the  dorsal  shields  are  provided  with  chalazae.  The  dark  plate- 
like spots  also  bear  chalazae  and  resemble  strumae.  The  mesothorax  and 
metathorax  are  subequal  in  length.  The  dorsal  surface  of  each  is  provided 
with  parascoli,  the  pinacula  of  which  have  grown  together  on  each  side  of 
the  mespn  to  form  a  basal  shield.  The  cephalic  portion  of  each  lateral 
aspect  of  the  mesothorax  bears  a  mesothoracic  spiracle,  the  metathoracic 
spiracle  of  each  side  is  rudimentary.  The  caudo-lateral  aspect  of  the  meso- 
thorax and  metathorax  are  each  provided  with  a  distinct  parascolus,  the 


40  ILLINOIS  BIOLOGICAL  MONOGRAPHS  [272 

mesothoracic  one  is  brown  and  the  metathoracic  one  is  white  or  cream- 
colored.  Each  thoracic  sternum  is  provided  with  a  pair  of  verrucae  ad- 
jacent to  the  meson.  The  terga  of  abdominal  segments  one  to  eight  are 
provided  with  black  or  brown  parascoli,  except  the  fourth,  in  which  the 
parascoli  are  orange  colored.  The  dorso-lateral  parascoli  of  segments  one 
and  four  are  also  yellow  or  orange  colored.  The  lateral  aspect  is  provided 
with  a  row  of  lateral  parascoli,  those  on  the  first  and  fourth  segments  are 
white  and  the  remainder  are  brown.  The  lateral  aspect  is  also  provided 
with  a  row  of  brown  paralateral  strumae  ventrad  of  the  lateral  parascoli. 
Sterna  two  to  nine  are  provided  with  a  transverse  row  of  four  verrucae 
on  each  segment,  sternum  one  bears  only  two  ventral  verrucae  which  are 
adjacent  on  the  ventro-meson,  the  ventro-lateral  verrucae  are  absent.  The 
dorsum  of  the  ninth  abdominal  segment  is  shield-shaped,  twice  as  long  as 
its  sternum,  and  provided  with  many  setae  or  chalazae.  The  legs  are  well 
developed  and  extend  beyond  the  sides  of  the  body.  The  tarsal  claw  is 
without  an  appendiculate  tooth. 

Hippodamia  13-punctata  Linn. — The  body  is  slender,  elongate,  widest 
at  the  metathorax.  The  dorsal  and  lateral  surfaces  are  provided  with 
parascoli.  The  general  color  is  brownish-tan  to  dark  grayish-brown  and 
the  head  is  darker  than  the  remainder  of  the  body.  The  head  is  heavily 
chitinized,  the  epicranial  arms  do  not  meet  but  extend  separately  to  the 
occipital  foramen.  The  mouth  is  directed  cephalo-ventrad.  The  pro- 
thorax  is  wider  than  long,  and  when  viewed  from  above,  is  oval  in  outline. 
Its  entire  surface  is  covered  with  a  solid  brown  dorsal  shield  which  has  a 
fine  white  line  running  along  the  dorso-meson.  The  cephalic,  lateral,  and 
caudal  margins  are  provided  with  distinct  chalazae.  The  mesothorax  is 
slightly  longer  than  the  metathorax,  about  twice  as  wide  as  long,  with  a 
distinctly  chitinized,  oval,  shield-shaped  struma  on  either  side  of  the 
meson.  This  struma  bears  ten  to  fifteen  chalazae.  The  metathorax  is 
more  than  twice  as  wide  as  long  and  provided  with  a  chitinized  shield-like 
struma  on  each  side  of  the  meson.  This  struma  bears  about  as  many 
chalazae  as  the  mesothoracic  strumae.  The  cephalic  portion  of  the  lateral 
aspect  of  the  mesothorax  and  metathorax  bears  the  thoracic  spiracles. 
The  mesothoracic  spiracles  are  prominent  and  are  located  in  the  mesocoria 
cephalo-dorsad  of  the  coxacoriae,  the  metathoracic  spiracles  are  rudimen- 
tary. The  caudal  portion  of  the  lateral  aspect  of  the  mesothorax  is  pro- 
vided with  a  brown  struma,  while  the  metathorax  is  provided  with  a  white 
struma.  Each  thoracic  sterna  is  provided  with  two  distinct  verrucae 
adjacent  to  the  ventro-meson.  The  legs  are  well  developed  and  extend 
beyond  the  sides  of  the  body.  The  tarsal  claw  is  without  a  distinct  appen- 
diculate tooth.  The  terga  of  abdominal  segments  one  to  eight  are  pro- 
vided with  distinct  dorsal  parascoli  located  near  the  dorso-meson,  those 
on  the  fourth  abdominal  segment  are  white.     The  lateral  margins  of  terga 


2731  THE  LARVAE  OF  THE  COCCJNELLIDAE— GAGE  41 

one  to  eight  bear  the  dorso-lateral  parascoli,  the  first  and  fourth  are  white 
and  the  remainder  are  brown  to  dark  tan-colored.  The  ninth  abdominal 
segment  is  longer  than  wide;  its  caudal  margin  is  acutely  rounded;  its 
dorsal  surface  is  brown  colored,  chitinized,  and  bears  many  chalazae  and 
small  setae.  The  lateral  aspect  of  segments  one  to  eight  is  provided  with 
distinct  lateral  strumae,  those  on  segments  one  and  four  are  white.  There 
is  a  small  paralateral  verruca  ventrad  of  each  lateral  strumae.  The  lateral 
aspect  of  the  ninth  segment  bears  chalazae.  The  sterna  of  segments  two 
to  nine  are  provided  with  four  chalazae  arranged  in  a  transverse  row  on 
each  segment,  the  sternum  of  the  first  segment  has  only  two  chalazae 
present,  the  ventrolaterals  are  wanting. 

Adalia  Mulsant 

This  genus  is  represented  in  the  material  studied  by  a  single  species. 

Adalia  bipunctata  Linn. — The  body  is  elongate,  oval  in  outline,  the 
third  and  fourth  abdominal  segments  are  the  widest.  The  general  color 
is  dark  brown  to  bluish-gray,  mottled  with  light  yellow  or  cream-colored 
spots.  The  dorsal  part  of  the  head  is  dark  brown  to  black  and  heavily 
chitinized,  while  the  ventral  portion  of  the  front  and  clypeus  is  white  or 
cream-colored.  The  epicranial  stem  is  absent  and  the  epicranial  arms 
curve  broadly  laterad  and  mesad  to  the  pretentorinae,  giving  the  front  a 
more  or  less  circular  appearance,  then  extend  laterad  from  the  pretentorinae 
toward  the  antacoriae  near  which  they  become  obsolete.  The  mouth  is 
directed  cephalo-ventrad.  The  prothorax  is  crossed  longitudinally  by  a 
median  and  two  lateral  yellow  stripes.  The  dorsal  shield  is  not  united  to 
the  meson  of  the  mesothorax  and  metathorax  and  the  two  portions  are 
separated  by  a  cream-colored  area.  The  lateral  aspect  of  the  prothorax  is 
glabrous.  The  cephalic  portion  of  the  mesothorax  and  metathorax  is  also 
glabrous;  while  the  caudal  portion  is  large  and  bears  a  small  but  distinct 
struma  on  each  segment.  The  mesothoracic  and  metathoracic  spiracles 
are  located  in  the  coriae  between  the  segments.  The  thoracic  sterna  are 
distinct,  each  sternum  bears  a  pair  of  small  verrucae  near  its  cephalic 
margin.  The  coxacoriae  are  distant.  Abdominal  segments  one  to  eight 
are  each  provided  with  a  transverse  row  of  four  strumae  on  the  tergum. 
The  mesal  portions  of  the  dorsal  strumae  of  the  fourth  segment  are  white, 
while  the  lateral  portions  are  brown,  the  dorso-lateral  strumae  of  the  first 
segment  are  surrounded  by  a  distinct  white  area,  and  the  dorso-lateral 
strumae  of  the  second  to  the  eighth  segments  are  surrounded  by  a  much 
smaller  white  area.  Each  struma  is  provided  with  three  to  five  prominent 
chalazae.  The  lateral  aspect  of  segments  one  to  eight  is  yellow  and  the 
strumae  are  brown  except  on  the  fourth  segment  where  they  are  light 
yellow.  There  is  a  small  but  distinct  chalaza  on  each  segment  ventrad  of 
the  lateral  strumae  of  segments  one  to  eight  which  is  surrounded  by  a  few 


42  ILLINOIS  BIOLOGICAL  MONOGRAPHS  [274 

setae  representing  the  paralateral  group.  The  ninth  tergum  is  shield- 
shaped,  longer  than  wide,  the  caudal  margin  concave  and  provided  with 
numerous  setae,  while  the  cephalic  margin  bears  only  a  few  chalazae. 
The  tenth  tergum  is  visible  from  the  dorsal  aspect  as  a  small,  brown 
colored,  chitinized  area  caudad  of  the  ninth  tergum  and  is  provided  with 
a  single  chalaza  on  each  side  of  the  meson.  Each  of  these  chalaza  is  sur- 
rounded by  a  group  of  small  setae.  The  ninth  sternum  is  about  one-half 
as  long  as  its  tergum,  deeply  emarginate  on  its  caudal  margin,  and  bears 
two  chalazae  on  each  side  of  the  meson,  each  of  which  is  surrounded  by  a 
few  setae.  The  tenth  sternum  is  longer  than  its  tergum  and  bears  a  dark 
colored  spot  near  the  lateral  margin.  The  legs  are  slender,  well  developed, 
and  longer  than  the  body  is  wide. 

Microweiseini 

The  body  is  small,  elongate,  fusiform,  depressed,  widest  at  tlie  meta- 
thorax,  provided  with  setae,  and  light-brown  to  yellowish-tan  colored. 
The  head  is  dark-brown  to  black  in  color  and  chitinized.  The  mouth  is 
directed  cephalo-ventrad  and  the  mandibles  are  unidentate.  The  epi- 
cranial arms  diverge  slowly  from  the  occipital  foramen  and  become  obsolete 
near  the  antacoriae.  The  spear-shaped  front  and  post-clypeus  are  divided 
on  the  meson  by  a  distinct,  dark  colored,  chitinized  bar  which  extends  from 
the  occipital  foramen  to  the  clypeo-labral  suture.  The  prothorax  is  oval 
and  slightly  wider  than  long;  while  the  mesothorax  and  metathorax  are 
distinctly  wider  than  long.  The  terga  of  the  thoracic  segments  are  longi- 
tudinally crossed  by  a  small  dark-colored  area  on  each  side  of  the  meson, 
more  distinct  on  the  prothorax  than  on  the  mesothorax  or  metathorax. 
The  ninth  abdominal  segment  is  conical,  narrower  than  the  eighth,  and 
about  twice  as  long  as  wide.  The  legs  are  well  developed  and  extend 
beyond  the  sides  of  the  body;  the  tibiae  are  provided  with  two  paddle- 
shaped  tenent  hairs  at  the  distal  end;  the  tarsal  claw  bears  a  distinct  appen- 
diculate  tooth;  and  the  coxacoriae  are  distant. 

MiCROWEiSEA  Cockerell 

This  genus  is  represented  in  the  material  studied  by  a  single  species. 

Microweisea  misella  Le  Conte. — The  body  is  fusiform,  elongate  and 
light-brown  to  yellowish-tan  in  color.  The  head  is  elongate,  dark  colored, 
and  chitinized.  The  epicranial  arms  are  present,  but  the  epicranial  stem 
is  wanting.  There  is  a  dark-brown  heavily  chitinized  bar  extending  along 
the  dorso-meson  from  the  occipital  foramen  to  near  the  clypeo-labral 
suture.  The  mouth  is  directed  cephalad.  The  prothorax  is  wider  than 
long  and  somewhat  oval  in  outline.  There  are  two  brown  chitinized  spots 
near  the  middle  of  the  dorsum  adjacent  to  the  meson.  The  dorsum  is 
provided  with  a  very  few  short  setae.     The  mesothorax  and  metathorax 


2751  THE  LARVAE  OF  THE  COCCI NELLl DAE— GAGE  43 

are  about  twice  as  wide  as  long;  and  the  lateral  margin  of  each  is  provided 
with  a  fringe  of  fine  setae.  The  sterna  of  the  thoracic  segments  are  equal 
in  size  to  that  of  their  respective  terga.  The  prosternum  appears  to  be 
glabrous;  while  there  is  a  pair  of  small  verrucae  adjacent  to  the  ventro- 
meson  of  the  metathorax  and  mesothorax.  These  verrucae  are  provided 
with  setae  which  are  about  as  long  as  their  segments.  The  coxacoriae  are 
distant  and  placed  near  the  lateral  margins  of  the  sterna.  The  legs  are 
small,  well  developed,  and  extend  beyond  the  sides  of  the  body.  Each 
tibia  is  provided  with  two  paddle-like  tenent  hairs  placed  near  the  distal 
end  of  the  segment,  the  tarsal  claw  bears  a  distinct  appendiculate  tooth. 
Abdominal  segments  one  to  eight  are  similar,  except  that  they  become 
successively  smaller.  Each  tergum  is  provided  with  a  few  small  setae 
which  are  never  as  long  as  the  segments.  The  dorsum  of  the  eighth  seg- 
ment is  dark,  chitinized,  and  its  caudal  margin  is  not  emarginate.  The 
sterna  and  the  lateral  aspects  of  segments  one  to  eight  are  similar  in  general 
size  and  structure.  They  are  membraneous  and  provided  with  a  few  small 
setae.  The  coriae  between  the  segments  are  distinct.  The  sternum  of  the 
eighth  segment  is  deeply  emarginate  on  its  caudal  margin.  The  ninth 
segment  is  longer  than  wide,  its  caudal  margin  narrower  than  the  cephalic. 
The  tergum  is  shield-shaped,  dark-colored,  chitinized,  and  the  caudal 
margin  is  acutely  rounded  and  bears  many  setae  about  one-half  as  long  as 
the  segment  is  wide.  The  shape  of  the  ninth  sternum  is  similar  to  that 
of  its  tergum,  it  is  very  slightly  chitinized  and  supplied  with  only  a  few 
setae.  The  tenth  segment  is  cylindrical,  directed  caudo-ventrad;  the  rec- 
tum is  evaginated  to  form  a  sucking  disk. 

Scymnini 
The  body  is  small,  elongate,  fusiform,  widest  caudad  of  the  metathorax, 
provided  with  verrucae  or  chalazae  and  setae,  and  light-yellow  to  light- 
brown  in  color.  The  head  is  slightly  chitinized,  light  colored,  densely 
setaceous,  and  directed  cephalad.  The  epicranial  suture  is  wanting. 
The  prothorax  is  oval,  slightly  chitinized,  and  provided  with  verrucae. 
The  mesothorax  and  metathorax  are  about  twice  as  wide  as  long  and  are 
provided  with  verrucae  on  the  dorsal  surfaces  and  with  chalazae  and  setae 
on  the  lateral  and  ventral  surfaces.  The  abdominal  segments  are  provided 
with  verrucae  on  the  dorsal  and  lateral  surfaces  and  with  chalazae  and  setae 
on  the  ventral.  The  ninth  abdominal  segment  is  cylindrical,  about  twice 
as  long  as  wide  and  the  sternum  is  shorter  than  the  tergum.  The  legs 
are  well  developed  and  extend  beyond  the  sides  of  the  body,  the  tibiae 
bear  more  than  two  tenent  hairs,  and  the  coxacoriae  are  distant. 

ScYMNus  Kugelann 
This  genus  is  represented  in  my  material  by  a  single  species  which  could 
not  be  determined. 


44  ILLINOIS  BIOLOGICAL  MONOGRAPHS  [276 

Scymnus  sp.? — The  body  is  fusiform,  elongate,  flattened,  Kght-yellow 
or  cream-colored  to  light-brown.  The  head  is  circular  in  outline,  very 
slightly  chitinized,  and  provided  with  numerous  black  setae  which  are 
about  one-half  as  long  as  the  body  is  .wide.  The  epicranial  suture  is 
entirely  wanting  and  the  mouth  is  directed  cephalad.  The  prothorax  is 
slightly  wider  than  long,  and  the  dorsum  bears  the  light-brown  slightly 
chitinized  dorsal  shield.  The  cephalic  margin  is  provided  with  six  large 
black  setae  which  are  about  one-third  as  long  as  the  segment,  the  caudal 
margin  has  six  setae  of  about  the  same  size  as  the  cephalic  setae,  but  not 
so  darkly  colored;  midway  between  the  cephalic  and  caudal  rows  there  is 
another  of  four  long  black  setae.  The  mesothorax  is  distinctly  narrower 
and  shorter  than  the  metathorax  which  is  broadly  emarginate  on  its 
caudal  margin.  Both  the  mesothorax  and  metathorax  have  an  oval- 
shaped  verruca  on  either  side  of  the  dorso-meson.  This  verruca  is  pro- 
vided with  setae  which  are  about  as  long  as  the  verruca  is  wide.  The 
thoracic  sterna  are  distinct.  Those  of  the  mesothorax  and  metathorax  are 
provided  with  a  few  setae;  while  the  prothoracic  sternum  is  glabrous. 
The  coxacoriae  are  distant  and  the  legs  are  well  developed,  usually  white 
or  light-yellow  in  color,  and  extend  beyond  the  margins  of  the  body. 
Each  tibia  is  provided  near  the  distal  end  with  six  to  eight  tenent  hairs.  The 
tergum  of  the  first  abdominal  segment  is  distinctly  longer  than  the  second. 
Each  tergum  of  abdominal  segments  one  to  eight  is  provided  with  a  trans- 
verse row  of  four  distinct  verrucae.  The  dorsal  verrucae  are  adjacent  to  the 
dorso-meson  and  the  dorso-lateral  are  near  the  lateral  margin  of  the  tergum 
in  each  segment.  The  lateral  aspect  of  segments  one  to  seven  is  lobed  and 
each  lobe  bears  a  distinct  verruca  with  setae  as  long  as  the  segment  bearing 
them.  The  lateral  aspect  of  the  eighth  segment  bears  two  or  three  chala- 
zae  about  as  long  as  the  setae  on  the  verrucae.  There  are  on  segments  two 
to  eight  one  or  two  distinct  paralateral  chalazae  immediately  ventrad  of 
the  lateral  verrucae  and  chalazae,  while  the  first  segment  bears  a  small 
paralateral  seta.  The  sterna  of  segments  one  to  eight  are  similar  to  their 
terga  in  size  and  shape.  The  cuticle  is  membraneous  and  bears  on  each 
segment  a  transverse  row  of  small  setae.  The  coriae  are  distinct.  The 
ninth  abdominal  segment  is  longer  than  wide,  slightly  chitinized,  and 
marked  with  a  dark  spot  near  the  middle  and  on  either  side  of  the  dorso- 
meson.  The  tergum  is  shield-shaped  and  provided  with  many  dark  colored 
setae.  The  lateral  aspect  of  the  segment  appears  to  be  glabrous.  The 
sterna  is  shorter  than  the  tergum,  the  cuticle  is  membraneous  and  armed 
with  a  transverse  row  of  four  small  setae.  The  tenth  abdominal  segment 
is  cylindrical,  glabrous,  directed  caudo-ventrad  and  bears  the  large  disk- 
like sucker. 


277]  THE  LARVAE  OF  THE  COCCINELLJDAE—GAGE  45 

Hyperaspini 
The  body  is  ovate  and  the  first  to  the  fourth  abdominal  segments  are 
widest.  The  prothorax  is  wider  than  long  and  the  caudal  margin  is  longer 
than  the  cephalic.  The  ninth  abdominal  segment  is  directed  ventrad, 
wider  than  long,  the  tergum  very  slightly  chitinized  and  provided  with  a 
few  small  setae.  The  body  is  usually  white  or  yellow  in  color.  The  larvae 
cover  themselves  with  flocculent  masses  of  wax-like  excretion.  The  body 
is  never  provided  with  scoli,  senti,  strumae,  or  verrucae,  but  is  usually 
armed  with  setae  or  small  chalazae.  In  the  early  larval  stages  the  epi- 
cranial suture  is  present,  while  in  the  adult  larval  stages  the  epicranial 
suture  is  wanting.  The  antennae  are  short,  three-segmented,  and  slightly 
setaceous.  The  mandibles  are  provided  with  a  slightly  developed  mola 
and  the  apex  is  never  bifurcate. 

Genera  of  Hyperaspini 

Cephalic  margin  of  the  prothorax  with  setae  about  as  long  as  the  pro- 
thorax  is  wide  and  lateral  tergal  abdominal  setae  are  about  twice  as 
long  as  the  segments  bearing  them Brachyacantha 

Cephalic  margin  of  the  prothorax  with  setae  which  are  not  as  long  as  the 
prothorax  is  wide  and  the  lateral  tergal  abdominal  setae  are  shorter 
than  the  segments  bearing  them Hyperaspis 

Brachyacantha  Chevrolat 

This  genus  is  represented  by  a  single  species. 

Brachyacantha  ursina  Fab. — The  dorsal  portion  of  the  head  is  slightly 
chitinized.  The  head  is  light  yellow  in  color;  the  mouth  is  directed  ventrad 
and  slightly  cephalad.  The  body  is  elongate,  widest  at  the  second  and 
third  abdominal  segments,  white  to  light-cream-colored,  usually  covered 
with  a  flocculent  wax-like  excretion.  The  prothorax  is  one-half  as  long 
as  wide.  The  dorsal  shield  is  wanting,  but  the  cephalic  margin  of  the 
prothorax  bears  eight  setae  which  are  longer  than  the  segment  is  wide,  the 
lateral  margin  bears  two  setae  which  are  also  longer  than  the  segment. 
The  lateral  aspect  is  poorly  defined  and  glabrous;  the  sternum  is  small 
and  without  setae.  The  mesothorax  and  metathorax  are  each  about  three 
times  as  wide  as  long,  are  provided  with  a  seta  near  the  lateral  margin 
which  is  longer  than  the  segment,  and  the  lateral  aspects  are  not  well 
defined.  The  mesothoracic  spiracles  are  located  in  the  mesocoria  near  the 
cephalic  margin  of  the  segment,  the  metathoracic  spiracle  is  wanting  or 
rudimentary.  The  legs  are  short  and  not  well  developed,  rarely  extending 
beyond  the  sides  of  the  body.  Abdominal  segments  one  to  eight  are 
similar.  The  terga  are  strongly  convex,  the  dorsal  and  dorso-lateral  setae 
are  longer  than  the  segments  bearing  them,  and  the  spiracles  are  located 
near  the  cephalo-ventral  margin  of  each  tergum.  The  lateral  aspect  of 
each  segment  is  provided  with  two  large  setae  which  are  not  longer  than 


46  ILUNOIS  BIOLOGICAL  MONOGRAPHS  [278 

the  segments  bearing  them,  the  lateral  setae  are  larger  than  the  paralateral 
ones.  The  sterna  are  flat;  each,  except  the  first,  bears  a  transverse 
row  of  four  large  setae.  In  the  first  segment  the  ventro-lateral  setae  are 
wanting.  The  caudal  margins  of  the  seventh  and  eighth  sterna  are  deeply 
emarginate.  The  tergum  of  the  ninth  segment  is  semicircular,  about  as 
wide  as  long,  and  the  dorsal  surface  is  densely  setaceous.  The  ninth 
sternum  is  small  and  bears  four  small  setae.  The  tenth  segment  is  small, 
cylindrical,  glabrous,  and  directed  ventrad. 

Hyperaspis  Redtenbacher 

The  members  of  this  genus  are  generally  white  to  cream-colored,  and 
the  body  is  usually  covered  with  a  flocculent  wax-like  mass.  When  seen 
from  the  dorsal  aspect,  the  body  is  oval  to  elongate  in  outline,  the  dorsum 
is  strongly  convex  and  the  sternum  is  more  or  less  flattened.  The  pro- 
thorax  is  wider  than  long  and  bears  setae  which  are  not  as  long  as  the  pro- 
thorax  is  wide.  The  ninth  abdominal  segment  is  semicircular,  wider  than 
long,  and  usually  retracted  into  the  eighth  segment.  The  legs  are  small, 
short,  and  well  developed.  The  mandibles  are  unidentate  and  serve  as 
piercing  organs.  The  members  of  this  genus  are  carnivouous  living  for 
the  most  part  upon  aphids  and  soft-bodied  coccids. 

Species  of  Hyperaspis 

Body  elongate-ovoid  and  densely  covered  with  dark  hair-like  setae 
H.  binotata 

Body  oval,  not  elongate,  apparently  glabrous,  but  with  a  few  small 

inconspicuous  setae H.  signata 

Hyperaspis  binotata  Say. — The  dorsal  aspect  of  the  body  is  brownish- 
yellow  to  yellowish-gray;  the  front,  vertex,  and  clypeus  are  spotted  with 
light  or  dark  brown  areas  and  provided  with  numerous  setae.  The  pro- 
thorax  is  about  twice  as  wide  as  long  and  the  cephalic  and  lateral  margins 
bear  setae  as  long  as  the  segment.  The  mesothorax  and  metathorax  are 
subequal  in  length,  but  the  latter  is  the  wider.  The  lateral  margin  of  the 
mesothorax  is  provided  with  a  group  of  setae  about  as  long  as  the  segment, 
while  the  lateral  margin  of  the  metathorax  has  a  distinct  chalaza  on  each 
side  which  is  surrounded  by  a  group  of  long  setae.  The  lateral  margins 
of  abdominal  segments  one  to  eight  are  each  provided  with  a  chalaza  sur- 
rounded by  a  distinct  group  of  setae.  The  dorsal  surface  of  the  thoracic 
and  abdominal  segments  are  densely  covered  with  short  black  setae.  The 
sterna  and  lateral  aspects  of  the  entire  larva  are  provided  with  numerous 
fine  and  inconspicuous  setae.  The  tergum  of  the  ninth  abdominal  seg- 
ment is  about  twice  as  wide  as  long,  not  strongly  chitinized,  and  the  caudal 
and  lateral  margins  bear  setae  which  are  longer  than  the  segment.  The 
sternum  is  about  one-half  as  long  as  the  tergum  and  deeply  emarginate  on 


279]  THE  LARVAE  OF  THE  COCCINELLIDAE—GAGE  47 

the  caudal  margin.  The  tenth  segment  is  small,  cylindrical,  and  slightly 
chitinized,  with  a  few  fine  setae  on  its  surfaces.  The  segment  is  usually 
directed  caudo-ventrad.  The  rectum  has  been  evaginated  to  form  a  suck- 
ing disk.  The  legs  are  short  and  well  developed,  but  do  not  extend  beyond 
the  sides  of  the  abdomen  in  the  adult  larvae.  The  coxacoriae  are  distant. 
Hyperaspis  signata  Oliv. — The  general  form  of  the  body  is  oval,  the 
dorsal  surface  is  globose.  The  body  is  usually  light-yellow  to  yellowish- 
green  in  color.  The  dorsal  aspect  of  the  head  is  brown,  tan,  or  yellowish 
gray.  The  cephalic  portions  are  spotted  with  small  brown  or  black  areas. 
The  head  is  provided  with  many  setae  which  are  usually  the  longest  setae 
found  on  the  entire  body.  The  tergum  of  the  prothorax  is  rectangular 
and  about  twice  as  wide  as  long.  The  dorsal  shield  is  wanting  and  the 
lateral  and  caudal  surfaces  are  provided  with  setae  which  are  about  as 
long  as  the  segment.  The  mesothorax  and  metathorax  are  subequal  in 
length,  but  the  metathorax  is  wider  than  the  mesothorax.  The  lateral 
margins  of  both  of  these  segments  are  provided  with  a  few  short  setae 
which  are  not  as  long  as  the  segment.  The  dorsal  aspect  of  abdominal 
segments  one  to  eight  are  similar  and  strongly  convex,  with  a  very  distinct 
coria  between  the  segments,  and  never  densely  setaceous  but  provided 
with  a  few  setae  which  are  never  as  long  as  the  segment  bearing  them. 
The  lateral  margin  of  the  dorsal  aspect  of  the  abdomen  is  provided  with 
a  series  of  lobes  between  the  annulets.  These  lobes  are  provided  with  a 
few  setae  which  are  not  as  long  as  the  segment.  The  sterna  and  the 
lateral  aspect  of  segments  one  to  eight  are  provided  with  a  few  short 
setae  which  are  almost  invisible.  The  tergum  of  the  ninth  abdominal  seg- 
ment is  more  or  less  shield-shaped,  more  than  twice  as  wide  as  long,  with 
the  caudal  margin  broadly  rounded.  The  lateral  and  caudal  margins 
bear  setae  which  are  not  as  long  as  the  segment.  The  ninth  sternum  is 
about  one-half  as  long  as  the  tergum,  its  cephalic  margin  is  broadly  convex 
while  the  caudal  margin  is  deeply  emarginate.  The  sternum  and  the 
lateral  aspects  are  provided  with  a  few  small  setae.  The  tenth  abdominal 
segment  is  retracted  into  the  ninth  so  that,  as  a  rule,  it  is  not  visible.  The 
tenth  segment  is  small,  circular,  and  membraneous.  The  rectum  is  eva- 
ginated to  form  a  sucking  disk.  The  legs  are  small,  dark  brown,  and  well 
developed,  but  do  not  extend  beyond  the  sides  of  the  body. 


48  ILLINOIS  BIOLOGICAL  MONOGRAPHS  [280 


BIBLIOGRAPHY 

Arrow,  Gilbert  J. 

1918.    Life  History  of  Scsonnus  capitatus.    Entom.    Monthly  Mag.,  54:    8-9. 
Banks,  Chas.  S. 

1906.    Principal  Insects  Attacking  Coconut  Palm  (Part  II).    Philippine  Jour,  Sd., 
211-228;  10  pis. 
Bexjtenmueller,  Wm. 

1891.    Bibliographical  Catalogue  of  the  Described  Transformations  of  North  American 
Coleoptera.    Jour.  N.  Y.  Micros.  Soc.,  7:1-52. 
Blatchley,  W.  S. 

1910.    An  illustrated  Descriptive  Catalogue  of  the  Coleoptera  or  Beetles  (Exclusive  of 
the  Rhynchophora)  Known  to  Occur  in  Indiana.  Indianapolis.  8vo.  Pp.  506-533. 
BOviNG,  Adam. 

1917.    A  Generic  Synopsis  of  the  Coccinellid  Larvae  in  the  United  States  National 
Musevun,  with  a  Description  of  the  Larvae  of  Hyperaspis  binotata  Say.    Proc. 
U.  S.  Nat  Museum,  51:621-650;  4  pis. 
Britton,  W.  E. 

1914.  Some  Common  Lady  Beetles  of  Coimecticut.    Bull.  Conn.  Agr.  Exp.  Sta,,  181, 
Ent.  Series  19:1-24. 

Casey,  Thos.  L. 

1899.    A  Revision  of  the  American  Cocdnellidae.    Jour.  N.  Y.  Entom.  Soc.,  7:71-169. 
Clausen,  C.  P. 

1915.  A  Comparative  Study  of  a  Series  of  Aphid-feeding  Coccinellidae.     Jour.  Econ. 
Entom.,  8:487-491. 

COMSTOCK,  J.  H. 

1893.    Evolution  and  Taxonomy.    Wilder  Quarter-Century  Book.    Pp.  37-113.    3  pis. 
CoMSTOCK,  J.  H.,  and  Kochi,  C. 

1902.    The  Skeleton  of  the  Head  of  Insects.    Amer.  Nat,  36:13-45. 

COQUEREL,  C. 

1849.    Observations  entomologiques  sur  divers  Coleopteres  recuellis  auz  Antilles.    Ann. 
soc.  ent.  France  (2),  7:441-454. 
DiMMOCK,  G.  W. 

1906.    Algunas  Coccinellidae  de  Cuba.    Primer  Informe  Anual  de  la  Estaci6n  Central 
Agron6mica  de  Cuba,  287-392;  3  pis. 
French,  G.  H. 

1883.    Preparatory  Stages  of  Epilachna  borealis,  Fab.    Can.  Entom.,  15:189-191. 
Ganglbauer,  L. 

1899.    Die  KSfer  von  Mitteleuropa.    8o.    VoL  3.    Pp.  941-1023. 
Hilton,  W.  A.    • 

1902.  The  Body  Sense  Hairs  of  Lepidopterous  Larvae.    Amer.  Nat,  36:561-578. 
Leng,  Charles  W. 

1903.  Notes  on  Coccinellidae.    Jour.  N.  Y.  Entom.  Soc,  11:35-45;  193-213;  2  pis. 
Letzner,  K. 

1857.    Beitrage  zur  Verwandlungsgeschichte  der  Coccinellen.      Zeit  f.  Ent,    11:3-24; 
IpL 


281]  THE  LARVAE  OF  THE  COCCJNELLJDAE—GAC^  49 

Lewcoce,  G.  a. 

1893.    Note  on  Cocdnella  ocellata,  L.    Entomolo^t,  26:249. 
Fauces,  Miriam  A. 

1914.    Some  Notes  on  Life  History  of  Ladybeetles.    Ann.  Ent.  Soc.  Amer.,  7:213-238; 
2  pis. 
SlUANTON,  F.  L. 

1916.    Hyperaspis  binotata,  A  Predatory  Enemy  of  the  Terrapin  Scale.    Jour.  Agri. 
Res.,  6:197-203;  2  pis. 

Weise,  Juuus. 

1879.    Bestimmungs-Tabellen    der    europfiischen    Coleoptem.      n.    Cocdnellidae. 
Zeitschr.  fOr  Ent.,  n.  F.  7:88-156. 


283]  THE  LARVAE  OF  THE  COCCI NELLI DAE— GAGE  51 


PLATE  I 


52 


ILUNOJS  BIOLOGICAL  MONOGRAPHS 


\m 


EXPLANATION  OF  PLATE 
CHILOCORUS  BIVULNERUS 


Fig.  1.  Larva,  dorsal  aspect. 
Fig.  2.  Larva,  lateral  aspect. 
Fig.  3.    Larva,  ventral  aspect. 


abdcof 

abdominal  coria 

tbdsp 

abdominal  spiracle 

ds 

clypeo-labral  suture 

CO 

coxacoria 

die 

dorsal  senti  group 

dise 

dorso-lateral  senti  group 

ds 

dorsal  shield 

fc 

front  and  postdypeus 

fuf 

furdnia 

I 

labrum 

he 

lateral  senti  group 

mi 

mandible 

micot 

mesocoria 

mspi 

mesopleural  area 

msst 

mesostemum 

mssp 

mesothoradc  spirade 

mst 

mesotergum 

mieor 

metacoria 

mtpl 

metapleural  area 

mta 

metastemum 

mU 

metatergnra 

mxpl 

maxUlaiy  palpus 

oc 

ocelli 

pc 

predypeus 

flse 

paralateral  senti  group 

pma 

points  of  musde  attachment 

pre 

procoza 

firco 

procoxacoria 

prd 

protarsaldaw 

prjr 

profemur 

Pfpl 

propletiral  area 

PfSt 

prostemum 

prta 

protarsus 

prti 

protibia 

prth 

prothoraz 

prtr 

protrochanter 

TP 

repugnatorial  pore 

sd 

sucking  disk 

St 

sternum 

i 

tergum 

Ose 

ventro-lateral  sent!  group 

tse 

ventral  senti  group 

ILLINOIS  BIOLOGICAL  MONOGRAPHS 


VOLUME  VI 


GAGE 


LARVAE  OF  THE  COCCINELLIDAE  PLATE  I 


2851  THE  LARVAE  OP  THE  C0CCINELLIDA3-GAGE  53 


PLATE  II 


54 


ILLINOIS  BIOLOGICAL  MONOGRAPHS 


[286 


EXPLANATION  OF  PLATE 

CEPHALIC  ASPECT^OF  THE  HEAD 

Fig.  4.  EpUackna  borealis. 

Fig.  5.  CkUocorus  bivulnerus,  lateral  aspect. 

Fig.  6.  CkUocorus  bivulnerus. 

The  label  els  for  the  clypso-labral  suture  is  wanting. 

Fig.  7.  Megilla  tnacidata. 

Fig.  8.  Hippodamia  13-punciata. 

Fig.  9.  Hippodamia  corner  gens. 


a 

antenna 

els 

ctjrpeo-labral  suture 

cs 

clypeal  suture 

ta 

epicranial  arms 

es 

epicranial  stem 

fc 

front  and  clypeus 

ta 

galea 

g« 

gena 

I 

labrum 

UU 

labialpalpus 
mandible 

md 

mco  mandacoria 

mxpl  maxillary  palpus 

oc  ocelli 

pc  predypeus 

pd  precoba 

pf  palpifer 

pt  pretentorina 

ss+ca  fused  stipes  and  cardo 

supt  supratentorina 

t  vertex 


ILLINOIS  BIOLOGICAL  MONOGRAPHS 


VOLUME  VI 


GAGE 


LARVAE  OF  THE  COCCINELLIDAE  PLATE  II 


2871  THE  LARVAE  OF  THE  COCCINELLIDAE—GAGE  S5 


PLATE  III 


56  ILLINOIS  BIOLOGICAL  MONOGRAPHS  (288 


EXPLANATION  OF  PLATE 
CEPHALIC  ASPECT  OF  THE  HEAD 


Fig.  10. 

Couindla  Q-notaia. 

Fig.  11. 

Anatis  15-punctata. 

Fig.  12. 

Adalia  bipunctata. 

Fig.  13. 

Microweisea  tnisella. 

Fig.  14. 

Scymnus  sp. 

Fig.  15. 

Hyperaspis  binotata. 

a          antenna 

mco 

mandacoria 

ch        clypeo-Iabral  suture 

oe 

ocelli  ^m 

cs         clypeal  suture 

PC 

preclypeat 

ea        epicranial  arms 

pa 

precoila 

fc         front  and  postclypeut 

pt 

pretentorins 

fe+v    front,  postclypeus  and  vertex 

9 

vertex 

/          labrum 

md       mandible 

ILLINOIS  BIOLOGICAL  MONOGRAPHS 


VOLUME  VI 


GAGE 


LARVAE  OF  THE  COCCINELLIDAE         PLATE  III 


289]  THE  LARVAE  OF  THE  COCCINELLIDAE—GAGE  57 


PLATE  IV 


58 


ILUNOIS  BIOLOGICAL  MONOGRAPHS 


1290 


EXPLANATION  OF  PLATE 

VENTRAL  ASPECT  OF  THE  HEAD 

fig.  16.    EpUachna  borealis. 

The  Label  Pg  for  the  palpiger  is  wanting. 
Pig.  17.    Chilocorus  bivulnerus,  caudal  aspect, 
fig.  18.    Chilocorus  bimdnerus. 
Fig.  19.    MegiUa  maculata. 

The  Label  su  for  the  submentum  b  wanting. 
Fig.  20.    Eippodamia  13-pundata. 

The  Label  lig  for  ligula  is  wanting. 
Pig.  21.    Eippodamia  convergens. 


a 

chidnoasband 

cp 

corpotentorium 

ta 

epicranial  arms 

a 

epicranial  saton 

I 

gula 

ga 

galea 

le 

gena 

lie 

labiacoria 

lit 

ligula 

upi 

labial  palpus 

mxpi  maxillary  paljxit 

of  occipital  forunen 

pf  palpiler 

pg  palpiger 

pt  pretentorina 
ss+ca  fused  sdpes  aod  cardo 

nt  submentum 

sup  supratentorium 

ts  tactile  setae 


ILLINOIS  BIOLOGICAL  MONOGRAPHS 


VOLUME  VI 


GAGE 


LARVAE  OF  THE  COCCINELLIDAE         PLATE  IV 


291]  THE  LARVAEfiF  TEE  COCCINELLIDAE—GAGE  59 


PLATE  V 


60  ILLINOIS  BIOLOGICAL  MONOGRAPHS  [292 


EXPLANATION  OF  PLATE 

VENTRAL  ASPECT  OF  THE  HEAD 

Fig.  22.  CoccineUa  9-notata. 

Fig.  23.  Anatis  15-punctata. 

Fig.  24.  Adalia  bipunctata. 

Fig.  25.  Microweisea  misella. 

Fig.  26.  Scymnus  sp. 

Fig.  27.  Hyperaspis  binotata. 

dt  clutinoas  band  mzc  maxacoria 

I  gula  mx^  maxillary  palpua 

ta  galea  pf  palfufei 

It  gena  ft  palpiger 

lie  labiacoria  M+ca  fused  stipes  and  caido 

Ht  ligula  su  submentom 

Upl  labial  palpus  U  tactile  letae 


ILLINOIS  BIOLOGICAL  MONOGRAPHS 


VOLUME  VI 


GAGE 


LARVAE  OF  THE  COCCINELLIDAE  PLATE  V 


2931  THE  LARVAE  OP  THE  COCCINELUDAEr-CAGE  61 


PLATE  VI 


^ 


tfl  ILLINOIS  BIOLOGICAL  MONOGRAPHS  [294 


EXPLANATION  OF  PLATE 

MISCELLANEOUS  PARTS  OF  THE  BODY 

Fig.  28.  Scolus,  EpUachna  borealis. 

Fig.  29.  Sentus,  Chilocorus  bivulnerus. 

Fig.  30.  Parascolus,  Hippodamia  convergens. 

Fig.  31.  Struma,  MegiUa  maculata. 

Fig.  32.  Verruca,  Microweisea  misella. 

Fig.  33.  Chalaza,  Hippodamia  convergens. 

Fig.  34.  Seta,  Hyperaspis  binohUa. 

Fig.  35.  Antenna,  EpUachna  borealis. 

Fig.  36.  Antenna,  Chilocorus  bivulnerus. 

Fig.  37.  Antenna,  Hippodamia  convergens. 

Fig.  38.  Antenna,  Hyperaspis  binotata. 

Fig.  39.  Antenna,  Scymnus  sp. 

Fig.  40.  Mandible,  Chilocorus  bivulnerus,  lateral  aspect. 

Fig.  41.  Mandible,  Chilocorus  bivulnerus,  mesal  aspect. 

Fig.  42.  Mandible,  Microweisea  misella. 

Fig.  43.  Tarsus,  Chilocorus  bivulnerus. 

Fig.  44.  Tarsus,  Microweisea  misella,  lateral  aspect 

Fig.  45.  Tarsus,  Microweisea  misella,  ventral  aspect. 

Fig.  46.  Tip  of  labial  palpus,  Chilocorus  bivtt^erus. 

Fig.  47.  Tentorium,  Chilocorus  bivulnerus. 

ant  antennaria  foa  postartif 

ante  antacoria  ^  pretentorium 

at  appendiculated  tooth  ps  preartis 

cp  corpotentorium  sc  scape 

ea  epicranial  arms  '                                                   S€  sensoria 

€S  epicranial  stem  sup  supratentorium 

d  denies  te  tarsal  daw 

Jl  flagellum  te  tenenthair 

met  metatentoria  ti  tibia 

mo  mola  ts  tactile  setae 

pd  pedicel 


ILLINOIS  BIOLOGICAL  MONOGRAPHS 


VOLUME  VI 


GAGE  LARVAE  OF  THE  COCCINELLIDAE         PLATE  VI 


Nrntural  History  6ttnF«f 
t^  Ukitarf 


